vis-convert should append to history from previous file

[d3v-null]

vis-convert history only contains history for the last command used on the file, despite the history being populated.

COMMENT Created by mwa_hyperdrive                                                                                                                                                                                                                            
COMMENT CmdLine: /pawsey/mwa/software/python3/hyperdrive/v0.3.0/bin/hyperdrive v                                                                                                                                                                             
COMMENT is-convert --data /scratch/mwaeor/dev/nfdata/1321447984/prep/birli_13214                                                                                                                                                                             
COMMENT 47984_2s_40kHz_edg80.uvfits --freq-average 80kHz --time-average 2s --out                                                                                                                                                                             
COMMENT puts birli_1321447984_2s_80kHz.ssins.uvfits --tile-flags Tile015 Tile035                                                                                                                                                                             
COMMENT  Tile045 Tile085 Tile088 Tile092 HexE2 HexE7 HexS11     

where the previous file had

HISTORY AIPS WTSCAL =  1.0                                                                                                                                                                                                                                   
COMMENT Created by birli 0.15.1                                                                                                                                                                                                                              
COMMENT CmdLine: /opt/cargo/bin/birli --avg-time-res 2 --avg-freq-res 40 --flag-                                                                                                                                                                             
COMMENT edge-width 80 -u birli_1321447984_2s_40kHz_edg80.uvfits -m 1321447984.me                                                                                                                                                                             
COMMENT tafits 1321447984_20211120125246_ch131_000.fits 1321447984_2021112012524                                                                                                                                                                             
COMMENT 6_ch132_000.fits 1321447984_20211120125246_ch133_000.fits 1321447984_202                                                                                                                                                                             
COMMENT 11120125246_ch134_000.fits 1321447984_20211120125246_ch135_000.fits 1321                                                                                                                                                                             
COMMENT 447984_20211120125246_ch136_000.fits 1321447984_20211120125246_ch137_000                                                                                                                                                                             
COMMENT .fits 1321447984_20211120125246_ch138_000.fits 1321447984_20211120125246                                                                                                                                                                             
COMMENT _ch139_000.fits 1321447984_20211120125246_ch140_000.fits 1321447984_2021                                                                                                                                                                             
COMMENT 1120125246_ch141_000.fits 1321447984_20211120125246_ch142_000.fits 13214                                                                                                                                                                             
COMMENT 47984_20211120125246_ch143_000.fits 1321447984_20211120125246_ch144_000.                                                                                                                                                                             
COMMENT fits 1321447984_20211120125246_ch145_000.fits 1321447984_20211120125246_                                                                                                                                                                             
COMMENT ch146_000.fits 1321447984_20211120125246_ch147_000.fits 1321447984_20211                                                                                                                                                                             
COMMENT 120125246_ch148_000.fits 1321447984_20211120125246_ch149_000.fits 132144                                                                                                                                                                             
COMMENT 7984_20211120125246_ch150_000.fits 1321447984_20211120125246_ch151_000.f                                                                                                                                                                             
COMMENT its 1321447984_20211120125246_ch152_000.fits 1321447984_20211120125246_c                                                                                                                                                                             
COMMENT h153_000.fits 1321447984_20211120125246_ch154_000.fits                                                                                                                                                                                               
COMMENT Msg: cable length corrections, digital gains, pfb gains, aoflagging with                                                                                                                                                                             
COMMENT  /usr/local/share/aoflagger/strategies/mwa-default.lua, geometric correc                                                                                                                                                                             
COMMENT tions                                                                                                                                                                                                                                                
SOFTWARE= 'birli 0.15.1'                                                                                                                                                                                                                                     
GITLABEL= 'v0.14.0 '