added section to how-it-works on contributing back to cargo

[rex-remind101]

addresses #942

[codecov]

Codecov Report

Merging #963 (0a3f85b) into main (a6fc428) will decrease coverage by 0.01%.
The diff coverage is n/a.

❗ Current head 0a3f85b differs from pull request most recent head b1ee37f. Consider uploading reports for the commit b1ee37f to get more accurate results

@@            Coverage Diff             @@
##             main     #963      +/-   ##
==========================================
- Coverage   78.41%   78.41%   -0.01%     
==========================================
  Files          64       64              
  Lines       14749    14731      -18     
==========================================
- Hits        11566    11551      -15     
+ Misses       3183     3180       -3     

see 6 files with indirect coverage changes

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[sunshowers]

Thanks! Did some editing but otherwise this looks great.