Login dialog displayed after successful mtls auth

### ⚠️ Before posting ⚠️

- [X] This is a **bug**, not a question or an enhancement.
- [X] I've [searched for similar issues](https://github.com/nextcloud/android/issues) and didn't find a duplicate.
- [X] I've written a clear and descriptive title for this issue, not just "Bug" or "Crash".
- [X] I agree to follow Nextcloud's [Code of Conduct](https://nextcloud.com/contribute/code-of-conduct/).

### Steps to reproduce

1. Use client cert to authentictate to nc.
2. See dialog that asks for additional login (here example in Polish):
3. See mobile session present in web UI.

### Expected behaviour

After successful authentication with client certificate, device should be authorized to use nc without any other confirmations, permissions, tokens, passwords.

### Actual behaviour

Login dialog is shown as above.

### Android version

up to date

### Device brand and model

-

### Stock or custom OS?

Stock

### Nextcloud android app version

4.6

### Nextcloud server version

28.0.4

### Using a reverse proxy?

Yes

### Android logs

_No response_

### Server error logs

_No response_

### Additional information

_No response_