Reach GitLab's groups to fill details about their feature flags

TL;DR

This issue described a method and execution for reaching respective groups to fill details of their YAML feature flags.

The intent is to have as many YAML feature flags to contain group: ownership, and if possible introduced_by_url: and rollout_issue_url:.

The idea is to follow this semi-automated processes:

enumerate all feature flags from the config/feature_flags/development/ and ee/config/feature_flags/development/
use regexp to find the most recent person that changed a line with that feature flag being used (in some cases it might not be 100% accurate)
create a list of feature flags with a @ayufan as a checkbox to ask a given individual to update the feature flag
notify individuals via TODOs and ask them to update group: field of YAML definition
an individual should open a very simple MR containing changes for only a given fields
it is desired for a single MR to have changes to many feature flags to reduce merge time
it is advised to update introduced_by_url: and rollout_issue_url: (if present)
it is not required to retroactively create rollout_issue_url:

This is the script that generates data: https://gitlab.com/-/snippets/2016367.

If you see your name for a given file, go ahead and update group: field
If you don't know anything about the given feature flag, feel free to ignore this
Open a single MR to update many feature flags, assign to any of maintainers directly for quick merge as soon as MR is green
Consider using WebIDE to edit many files in bulk
Mark a checkbox on this page once you did it
If possible additionally update introduced_by_url: and rollout_issue_url:
Do not spend time to retroactively create rollout_issue_url: unless you consider this useful