refactor: apply black on wily codebase

[skarzi]

There is one action to do when this commit will be squashed to the main branch:

• add squashed commit with this PR to .git-blame-ignore-revs like suggested in black docs

[codecov-commenter]

Codecov Report

Merging #162 (56939c0) into master (cd3f049) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #162   +/-   ##
=======================================
  Coverage   95.23%   95.23%           
=======================================
  Files          23       23           
  Lines        1216     1216           
  Branches      291      291           
=======================================
  Hits         1158     1158           
  Misses         33       33           
  Partials       25       25           

Impacted Files	Coverage Δ
src/wily/cache.py	98.18% <ø> (ø)
src/wily/operators/maintainability.py	100.00% <ø> (ø)
src/wily/archivers/git.py	87.50% <100.00%> (ø)
src/wily/commands/report.py	97.00% <100.00%> (ø)
src/wily/lang.py	100.00% <100.00%> (ø)

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[tonybaloney]

Thanks!