Refresh hooks when refreshing extensions.

[scidomino]

Summary

Refresh hooks when refreshing extensions

Details

Also:

• removed unnecessary initialization protection from hooks. HookSystem.initialize() is only called from config.initialize() which already has protections against multiple calls.
• removed .integration-test file that was accidentally merged in a previous PR.

Related Issues

Fixes #14531

How to Validate

Uninstall an extension with a hook and verify that it no longer gets called.

Pre-Merge Checklist

• [ ] Updated relevant documentation and README (if needed)
• [ ] Added/updated tests (if needed)
• [ ] Noted breaking changes (if any)
• [ ] Validated on required platforms/methods:
  • [ ] MacOS
    • [x] npm run
    • [ ] npx
    • [ ] Docker
    • [ ] Podman
    • [ ] Seatbelt
  • [ ] Windows
    • [ ] npm run
    • [ ] npx
    • [ ] Docker
  • [ ] Linux
    • [ ] npm run
    • [ ] npx
    • [ ] Docker