feat(rust): allow specifying features to `cargo metadata`

[melotic]

Closes #1001

This uses a new environment variable to configure the Rust CLI detector, CD_RUST_CLI_FEATURES. Open to any other ideas on how to pass this into the detector.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Comparison is base (c2cfd4d) 75.3% compared to head (99e9102) 75.3%.

Additional details and impacted files

@@          Coverage Diff          @@
##            main   #1009   +/-   ##
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  Coverage   75.3%   75.3%           
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  Files        236     236           
  Lines      10353   10357    +4     
  Branches    1025    1026    +1     
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+ Hits        7800    7804    +4     
  Misses      2269    2269           
  Partials     284     284           

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[cobya]

I think it's time to start investing in a file-based configuration approach where we have a top-level service read a file from something like .detection/config.json where we keep these environment variables, but that would probably be outside the scope of this 🤨