feat: CSS contain-intrinsic-* syntax updates

[bsmth]

This PR updates the syntax for all contain-intrinsic-* properties:

• Most adhere to auto? [ none | <length> ] -> an optional auto keyword followed by none or a <length>, e.g.:
  • 10px
  • auto none
  • auto 300px
• [ auto? [ none | <length> ] ]{1,2} - an optional auto keyword with none or a <length>,
  • 50px 250px
  • none none
  • can be auto 10px auto 10px (for auto width, auto height)

Additionally setting all of these as standard now.

Related issues and pull requests:

• [ ] Parent issue https://github.com/mdn/content/issues/28292
• [ ] Examples: https://github.com/mdn/content/pull/28618
• [x] Relnote https://github.com/mdn/content/pull/28522
• [x] BCD - https://github.com/mdn/browser-compat-data/pull/20532

Bugzilla:

• https://bugzilla.mozilla.org/show_bug.cgi?id=1835813