Replaces all the explicit include metadata syntax in the specs (tag:
true) into the implicit one (:tag).
Added a cop to prevent future errors and handle autocorrection.

Signed-off-by: Rémy Coutable <remy@rymai.me>

Signed-off-by: Rémy Coutable <remy@rymai.me>

added key to assignee avatar loop

This is to improve reliability on mentioned tests

Removed all the unnecessary include of `WaitForAjax` and `ApiHelpers` in the specs.
Removed unnecessary usage of `api:true`

- Uses Timecop to fix due date spec
- Waits for sidebar to be visible before doing anything
- Fixes weird issues where the link would be clicked instead of the card itself

Closes #28310

CHANGELOG item

Closes #26514