Multiple Admin Interface fixes and some others.

Misc:
- Fixed hadolint workflow, new git cli needs some extra arguments.
- Add ignore paths to all specific on triggers.
- Updated hadolint version.
- Made SMTP_DEBUG read-only, since it can't be changed at runtime.

Admin:
- Migrated from Bootstrap v4 to v5
- Updated jquery to v3.6.0
- Updated Datatables
- Made Javascript strict
- Added a way to show which ENV Vars are overridden.
- Changed the way to provide data for handlebars.
- Fixed date/time check.
- Made support string use details and summary feature of markdown/github.