Update deprecation and removal templates and content

What does this MR do and why?

This MR updates our deprecation and removal content guidelines in order to make those announcements actionable.

For a detailed account of the problem and proposed solution, see gitlab-com/www-gitlab-com#14106 (closed)

Changes in this MR

• Adds guidance to the templates that deprecation and removal announcements should be actionable
• Changes the "name" field to "title" in all Dep/Rem .yml files to reinforce that an announcement shouldn't just list the feature name being deprecated or removed, it should be an actionable title
• Updates the compilation scripts to account for the changed field name

Template updates

There are a lot of .yml changes in the diff. The noteworthy changes to the guidelines can be reviewed in:

• data/deprecations/templates/example.yml
• data/removals/templates/example.yml

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.