Documentation displays outdated login domain (@ai-dev.brreg.no) causing missing portal permissions for secrets

### Description

Under _**Apps infrastructure access**_ there's a section - as shown below - about what the users login til be for the Microsoft Azure Portal. The login `username@ai-dev.brreg.no` seems to be an expired version, where `username@ai-dev.no` is the new one.
If a user wants to add secrets to their repo, and have previously used `username@ai-dev.brreg.no` to log in, they won't see anything in the portal.
The user has to contact Altinns Servicedesk about this so they can change it for them. This should be mentioned so the user understand why they don't see anything in the portal.

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_For login you use the same account as for the portal:_

- _`username@ai-dev.no` (most people)_
- _`username@ai-dev.brreg.no` (a few still uses this)_

### Additional Information

_No response_

Search the documentation for the outdated `username@ai-dev.brreg.no` login and the “Apps infrastructure access” section. Update the login guidance to use `username@ai-dev.no` and explain that users with the old account must contact Altinns Servicedesk to restore portal access; done when the section reflects the current login and missing-permissions case.

Written by the indexing model from the issue text.