fix: dart-code-metrics crash saying Bad state: No element when running command

[fzyzcjy]

Hi thanks for this flutter-favorite package! It is crashing because of .max on empty array. So here is the fix.

Closes #804

[incendial]

@fzyzcjy thanks again for you contribution! Can you please update the changelog too?

[incendial]

Now formatting is broken, can you fix that too?

[fzyzcjy]

@incendial Done

[codecov]

Codecov Report

Merging #805 (6c6c50a) into master (240d317) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #805   +/-   ##
=======================================
  Coverage   87.26%   87.26%           
=======================================
  Files         277      277           
  Lines        5898     5898           
=======================================
  Hits         5147     5147           
  Misses        751      751           

Impacted Files	Coverage Δ
...rc/analyzers/lint_analyzer/utils/report_utils.dart	100.00% <100.00%> (ø)

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[fzyzcjy]

Look forward to releasing a new version :)

[incendial]

Plan to release it tomorrow 👍

[fzyzcjy]

looking forward to the release!