Offboarding checklist for @tadhg-ohiggins

For everyone

[x] Remove from Google groups as applicable:
- [x] FAC-team
- [x] fac-gov-test-users
- [x] fac-gov-api-dev
[x] Remove from the FAC team in GitHub
[x] Remove from the private channels #oros-fac-private and #fac-helpdesk in Slack (“/remove @[person]”)
[x] Remove from active Figma projects
[x] Remove from Mural
[x] Remove from Zendesk
[x] Check for and remove admin access in the FAC application: this may include designated permissions and/or checked-in API access (for example)

[x] Make a PR to remove the departing team member from the list of developers and managers with access to our spaces.
[x] Remove the departing team member as a member of the FAC group in New Relic. (@GSA-TTS/fac-admins can do this)
- [ ] If they're leaving TTS altogether, also delete their account.

[x] If the departing team member is a Google Group manager, designate a new manager for any groups they manage.
[x] If they are the on Make someone else the Maintainer and remove the departing team member from the FAC-admins team in GitHub and the FAC-team team in GitHub.
[x] Remove any deployment tokens associated with the PL/PO from the repository.