Fallback to branch protections when rulesets unavailable

[ajhenry]

Describe the bug

There's currently a known issue where EMU integrations are not allowed to create repository rulesets. We need to fallback to using branch protections until this issue is resolved.

To Reproduce

When making rulesets in an EMU org, you will be met with the following error:

{"data":{"createRepositoryRuleset":null},"errors":[{"type":"FORBIDDEN","path":["createRepositoryRuleset"],"extensions":{"saml_failure":false},"locations":[{"line":1,"column":11}],"message":"Unauthorized: As an Enterprise Managed User, you cannot access this content"}]}

Expected behavior

We need to use the old behavior of branch protections when this error occurs

Screenshots

No response

Additional context

No response

[sutterj]

@ajhenry Is this ready to be closed?