v1.9.0: 🌎 region & config

Improvements for users:

• Use Mac App Store region throughout, instead of using it in some places & the macOS region in others (#689 by @rgoldberg)
• Add mas region command: displays the region of the Mac App Store (#689 by @rgoldberg)
• Add mas config command: displays mas config & related system info, mainly for bug reports (#698 & #702 by @rgoldberg)
  • Update Bug Report form (#700 by @rgoldberg):
    • Modify to expect config info from mas config
    • Simplify the input fields & instructions
• Whenever an app name is missing, substitute the same fallback property values throughout mas (#690 by @rgoldberg)

Improvements for developers:

• Append a + to version name if there are any uncommitted changes or unignored untracked files (#688 & #704 by @rgoldberg)
• Cleanup code (#687 & #692 by @rgoldberg)
• Improve linting (#697 by @rgoldberg)
• Avoid build warning on newer swift compilers (#697 by @rgoldberg)
• Improve testing (#695 by @rgoldberg):
  • Check all consequences for correctness:
    • return value
    • error
    • stdout
    • stderr
  • Remove useless tests
  • Cleanup tests

Improvements for administrators:

• GitHub workflows (#691 by @rgoldberg):
  • Scan for vulnerabilities with CodeQL workflow (#646 by @rgoldberg)
  • Scan for Swift library updates with Dependabot workflow
  • Remove useless Danger workflow
  • Minimize granted permissions
  • Cleanup logs

Full Changelog: v1.8.8...v1.9.0