UX/Translation changes:
- new teams: remove redundant tooltips that don't add meaningful information
- move general information to table fieldset
- new teams: rename "general" to "custom" access for clarity
- new teams: show labels beside options on mobile
Accessibility:
- semantic form elements allow easier navigation (fieldset, mostly)
- improve better labelling of new teams table
- fix accessibility scan issues
- TODO: the parts that "disable" form elements were not yet touched and
are not really accessible to screenreaders
Technical:
- replace two JavaScript solutions with one CSS standard
- implement a simpler grid (.simple-grid)
- simplify markup
- remove some webhook settings specific CSS
Testing:
- check more form content for accessibility issues
- but exclude tooltips from the scan :(
- reuse existing form tests from previous PR
