Offboard UsabilityHub from Tech Stack

Tech Stack Update

This update removes UsabilityHub from the tech stack. It was identified as a system that is not longer being used at GitLab during the FY22 Business Impact Analysis that was completed earlier in FY22Q3

Please do not merge this MR before the Business Systems Analysts have reviewed and approved.

Please take into account:

• If changing provisioners: You must also open an Update Tech Stack provisioner issue so all templates and Tech Stack information can be updated.
• If completing a system offboarding:
  • Follow the steps in the Tech Stack offboarding section

/cc @lisvinueza