Clean up code

[Luni-4]

This PR fixes clippy warnings introduced by Rust 1.60 and hides downloaded repositories from git

[codecov-commenter]

Codecov Report

Merging #824 (956e217) into master (0cc9bcd) will decrease coverage by 0.39%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #824      +/-   ##
==========================================
- Coverage   41.32%   40.92%   -0.40%     
==========================================
  Files          51       51              
  Lines        7100     7088      -12     
  Branches     1011     1011              
==========================================
- Hits         2934     2901      -33     
- Misses       3471     3486      +15     
- Partials      695      701       +6     

Impacted Files	Coverage Δ
src/ops.rs	81.81% <100.00%> (-1.15%)	⬇️
src/node.rs	71.15% <0.00%> (-15.39%)	⬇️
src/getter.rs	74.68% <0.00%> (-3.74%)	⬇️
src/spaces.rs	71.08% <0.00%> (-1.21%)	⬇️
src/metrics/nargs.rs	74.71% <0.00%> (-0.77%)	⬇️
rust-code-analysis-cli/src/main.rs	0.41% <0.00%> (-0.01%)	⬇️
src/tools.rs	55.00% <0.00%> (+0.22%)	⬆️
src/langs.rs	100.00% <0.00%> (+10.00%)	⬆️

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