docs: Abstract component guideline MR template
As part of #1164 (closed), we're updating the contribution resources to account for Objects.
This MR abstracts the component guideline MR template to be generic, applicable to any kind of documentation change.
- Renames the MR template name to
Documentation
. - Fixes broken links.
- Rewords the acceptance criteria checklist items.
- Reorders some of those list items to a more appropriate place.