fix(gradle): Fixed broken handling of test server and credentials

[PhilLab]

This was a refactoring error from a17e138

• Tests written, or not not needed

[PhilLab]

@tobiasKaminsky

1. For what its worth, I also had other build troubles caused by the Gradle update, but I didn't include them in the PR here, because their solution is less obvious: App build fails in encrypted Linux home dir since upgrade to AGP 9 #16421
2. I am not exactly sure what it means that the PR I am hereby amending: chore(agp): Android Gradle plugin 9.0.0  #16306 , was added to the 3.36.0 milestone. Maybe the fix here should be in the milestone as well, if this is required to be part of the release code.

[github-actions]

APK file: https://www.kaminsky.me/nc-dev/android-artifacts/16422.apk



To test this change/fix you can simply download above APK file and install and test it in parallel to your existing Nextcloud app.

[github-actions]

blue-Light-Screenshot test failed, but no output was generated. Maybe a preliminary stage failed.