Introduce BeyondIdentity integration to verify GPG keys
What
BeyondIdentity is an instance level integration. When it's activated, only the GPG keys that were issued by BeyondIdentity service are accepted.
Related issue: [MVC] Beyond Identity integration (#431433 - closed)
Why
It requires small changes to introduce a new integration into our existing Integrations mechanism: https://docs.gitlab.com/ee/user/project/integrations/index.html
- Introduces a new Integration that automatically provides the UI for setting it up on instance level
- Reject a GPG key if it hasn't been issued by Beyond Identity Authenticator
Edited by Igor Drozdov