[TASK] Tests: Activate ext:rsaauth test suite

The test suite of ext:rsaauth is missing in UnitTests.xml, add it.

Resolves: #58531
Related: #58530
Related: #51436
Releases: 6.2
Change-Id: I5c1c8bbf415ed53270a09bdf68df300e28eb5f09
Reviewed-on: https://review.typo3.org/29878
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn