Update UI tests

[dzolnai]

• They were not running on API level 34 because of a missing permission declaration in the testing libraries. Updating the libraries fixed this.
• The eduID website and Chrome introduction screen changed a bit
• I have moved the browser preparation code to a common class, to reduce duplication
• I have also found a timing issue, where sometimes the common cookie would be canceled before the reply was sent, aborting the process of adding a new server