Improve react-testing-library user-event extension usability (with PatternFly)

Description of problem:

With ODC-5851 we introduced react-testing-library (or the "testing-library") to our code.

We also added the official "user-event" extension (https://testing-library.com/docs/ecosystem-user-event/) which provides additional functions to simulate browser events. For example it can simulate that a user types a text into an input field (focus, multiple key events, blur event and change event) instead of just firing one single onChange event.

This is really useful but it doesn't work well with our InputFields from @console/shared and TextInput from PatternFly.

Actual results:

userEvent.type(inputField) fails

Expected results:

userEvent.type(inputField) should work

Additional notes

As part of this PR the workaround in packages/dev-console/src/components/buildconfig/_tests_/user-event.ts should be removed and replaced with the @testing-library/user-event library.