Change behaviour in auth method detection

After typing server URL in login view, a request to /remote.php/dav/files/

Then, check WWW-Authenticate headers in response

Current behaviour:

https://github.com/owncloud/android/blob/02a321e14a9a915a92b7c8f40afe235e48388882/owncloudApp/src/main/java/com/owncloud/android/presentation/authentication/LoginActivity.kt#L327

First, we check if is basic, if not, check if it's bearer, then OIDC...

New behaviour:

Contains Bearer ➡ OAuth 2.0 / OpenID Connect
Doesn’t contain Bearer ➡ Basic

Also, in case the WWW-Authenticate header contains any other string that's not Bearer or Basic , we should show a readable error message. Now:

OCP\Session\Exceptions\SessionNotAvailableException: Session has been closed - no further changes to the session are allowed

More context in:

• https://github.com/owncloud/enterprise/issues/5991

TASKS

• Research (if needed)
• Create branch feature/feature_name
• Development tasks
  • Implement whatever
  • ...
• Code review and apply changes requested
• Design test plan
• QA
• Merge branch feature/feature_name into master

PR

• App
• Library (if needed)

Start in owncloudApp/src/main/java/com/owncloud/android/presentation/authentication/LoginActivity.kt around line 327, where the authentication method is detected after the DAV request. Trace how the WWW-Authenticate header is handled. Done means Bearer selects OAuth 2.0/OpenID Connect, headers without Bearer select Basic, and unsupported values produce a readable error instead of the current exception.