SSO login fails if no group claim included when expected

### Current Behavior

If an email domain has SSO enabled with managed team membership enabled, but the login claim is missing the group claim, the login will fail.

We have seen a case with Azure where a user was not a member of any group, so the login did not include any group claim and an error was thrown.

For this scenario, I think we should log that no group claim was found (as that's helpful to debug misconfigurations), but if 'allow user to be a member of other teams' is enabled, they should still be able to login and the missing claim treated as an empty list.

### Expected Behavior

User can still login

### Steps To Reproduce

_No response_

### Environment

- FlowFuse version:
- Node.js version:
- npm version:
- Platform/OS:
- Browser:

### Have you provided an initial effort estimate for this issue?

I have provided an initial effort estimate