ノートの添付ファイル選択時に複数のファイルを同時に選択できるように

[poppingmoon]

アップロードするファイルを選択するときに複数選択できるようにFilePickerで指定しました

ドライブからファイルを複数選択できるように、ダイアログを変更しました

Fix #362

[codecov-commenter]

Codecov Report

Merging #369 (46b47ba) into develop (c30e96b) will increase coverage by 0.29%.
The diff coverage is 73.52%.

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@@             Coverage Diff             @@
##           develop     #369      +/-   ##
===========================================
+ Coverage    23.70%   24.00%   +0.29%     
===========================================
  Files          216      216              
  Lines        10460    10498      +38     
===========================================
+ Hits          2480     2520      +40     
+ Misses        7980     7978       -2     

Files	Coverage Δ
lib/model/image_file.dart	80.00% <100.00%> (ø)
...ib/view/note_create_page/file_settings_dialog.dart	0.00% <0.00%> (ø)
...iew/note_create_page/drive_file_select_dialog.dart	71.73% <78.43%> (+8.50%)	⬆️
...r/note_create_page/note_create_state_notifier.dart	75.34% <72.34%> (+1.20%)	⬆️

... and 1 file with indirect coverage changes

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[shiosyakeyakini-info]

マージしました！