Test add migrations to release post

This MR is just a test on top of !108230 in order to preview an example of adding a migrations list.

Any suggested revisions will be made in that MR and pulled into this one.

Preview

• If migrations objects are provided via .yml files in the data/x_y directory, a Migrations section will be included in the release post with the other tertiary items (Bugs, Performance, UX): Example
• If no migrations objects are present, the section simply isn't displayed: Example

Usage

• In order to add a migrations listing, a tertiary object with a name of "Migrations" is added to the data/x_y directory following the same pattern as Bug Fixes, Performance Improvements, and Usability Improvements.
• An example file has been provided at: data/release_posts/unreleased/samples/migrations.yml

Question

• Should this file be added to the automation and created in every release? Or should we add a Todo to ping @sam.white (or other relevant DRI?) to create a "Migrations" listing if there are any to be announced?

Author Checklist

• Provided a concise title for this Merge Request (MR)
• Added a description to this MR explaining the reasons for the proposed change, per say why, not just what
  • Copy/paste the Slack conversation to document it for later, or upload screenshots. Verify that no confidential data is added.
• Assign reviewers for this MR to the correct Directly Responsible Individual/s (DRI)
  • If the DRI for the page/s being updated isn’t immediately clear, then assign it to one of the people listed in the Maintained by section on the page being edited
  • If your manager does not have merge rights, please ask someone to merge it AFTER it has been approved by your manager in #mr-buddies
• If the changes affect team members, or warrant an announcement in another way, please consider posting an update in #whats-happening-at-gitlab linking to this MR
  • If this is a change that directly impacts the majority of global team members, it should be a candidate for #company-fyi. Please work with internal communications and check the handbook for examples.

---