Remove `design_management_todos_api` feature flag
:design_management_todos_api feature flag added in !16885 (merged).
- Team: group::knowledge
- Most appropriate slack channel to reach out to:
- Best individual to reach out to: @.luke
### What are we expecting to happen?
As the FF is
default_enabled, we expect nothing to happen.
Roll Out Steps
- [-] Enable on staging
- [-] Test on staging
- [-] Ensure that documentation has been updated
- [-] Enable on GitLab.com for individual groups/projects listed above and verify behaviour
- [-] Announce on the issue an estimated time this will be enabled on GitLab.com
- [-] Enable on GitLab.com by running chatops command in
- [-] Cross post chatops slack command to
#support_gitlab-comand in your team channel
- [-] Announce on the issue that the flag has been enabled
- Remove feature flag and add changelog entry
After the flag removal is deployed, clean up the feature flag by running chatops command in