feat: add version flag to print package version

[incendial]

What is the purpose of this pull request? (put an "X" next to an item)

[ ] Documentation update
[ ] Bug fix
[ ] New rule
[ ] Changes an existing rule
[ ] Add autofixing to a rule
[X] Add a CLI option
[ ] Add something to the core
[ ] Other, please explain:

[github-actions]

Dart Code Metrics unused files report of dart_code_metrics. ✅

Summary

• Scanned package folders: bin, example, lib
• No unused files found! ✅

[codecov]

Codecov Report

Merging #660 (93b01b7) into master (30db896) will increase coverage by 0.06%.
The diff coverage is 73.33%.

@@            Coverage Diff             @@
##           master     #660      +/-   ##
==========================================
+ Coverage   86.15%   86.21%   +0.06%     
==========================================
  Files         251      251              
  Lines        5367     5377      +10     
==========================================
+ Hits         4624     4636      +12     
+ Misses        743      741       -2     

Impacted Files	Coverage Δ
lib/src/cli/cli_runner.dart	62.50% <73.33%> (+26.13%)	⬆️

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[github-actions]

Dart Code Metrics analyze report of dart_code_metrics. ✅

Summary

• Scanned folders: bin, example, lib, test

• Total scanned files: 381

• Total lines of source code: 6832

• Total classes: 255

• Average Cyclomatic Number per line of code: 0.35 / 1

• Average Source Lines of Code per method: 6

• Total tech debt: 1094.0 hours

• Found issues: 6 ⚠