Update testing-utitlities

[JohannesDoberer]

Our testing-utilities documentation references to angular protractor. Protractor is deprecated and reached end-of-life by Summer 2023.

Running ng e2e suggests:

• Cypress
• Nightwatch
• WebdriverIO
• Puppeteer

TBD: Maybe we should document an example based on own of these frameworks.

Check if there is a dependency to protractor lib (codewise).