fix(developer): improve warnings around keyboard version matching

Fixes #9145.

* `WARN_KeyboardVersionsDoNotMatch` is now only raised when
  `FollowKeyboardVersion` is set.
* `WARN_KeyboardVersionsDoNotMatchPackageVersion` has been removed,
  because it did not really make sense; if 'FollowKeyboardVersion' is
  set, it could not be raised, and otherwise, the author may wish to
  have separate keyboard + package versions anyway.
* Note that the 0x0013 compiler message allocation for
  `WARN_KeyboardVersionsDoNotMatchPackageVersion` has been left alone;
  as this was only used in pre-release, we can probably re-task it in
  the future.