[FEATURE] Provide UnitTest.xml with code coverage generation

This patch provides a basic setup for running extbase unit
test through one xml file that also collects code coverage
data whoose output will be stored in Build/Coverage.

Releases: 6.1
Resolves: #44601
Change-Id: I51f5c4c85d22a82848172b4716267d08d1b2f0f5
Reviewed-on: https://review.typo3.org/17576
Reviewed-by: Ingo Pfennigstorf
Tested-by: Ingo Pfennigstorf
Reviewed-by: Anja Leichsenring
Tested-by: Anja Leichsenring
[TASK] Provide Unit Test for Error/Message

Releases: 6.1
Resolves: #44603
Change-Id: Iceb69ccb6b5097cf6c8cf9d7ff0d3fe440ac9d8e
Reviewed-on: https://review.typo3.org/17578
Reviewed-by: Wouter Wolters
Tested-by: Wouter Wolters
Reviewed-by: Anja Leichsenring
Tested-by: Anja Leichsenring