docs: updates frontmatter to reflect latest stage and group

Description

This MR updates the metadata in the frontmatter of the various markdown files to reflect the latest stage and group names (devopsai-powered and groupeditor extensions)

Reference: https://gitlab.com/gitlab-com/www-gitlab-com/-/blob/master/data/stages.yml

How has this been tested?

N/A

Screenshots (if appropriate)

N/A

What CHANGELOG entry will this MR create?

• fix: Bug fix fixes - a user-facing issue in production - included in changelog
• feature: New feature - a user-facing change which adds functionality - included in changelog
• BREAKING CHANGE: (fix or feature that would cause existing functionality to change) - should bump major version, mentioned in the changelog
• None - other non-user-facing changes