[TASK] Raise testing-framework to 2.0.0

master branch of testing-framework is now tagged as 2.x.x for
core master / v9, while the 8 branch of testing-framework
is tagged as 1.2.x and used in v8 core.
The split is needed since master branch contains the svg tree
adaptions and 1.2 branch does not.

Change-Id: I27bb4e996e20cf00110cb0e6a160337656a2d7f0
Resolves: #83203
Related: #83204
Related: #82226
Related: #82426
Releases: master
Reviewed-on: https://review.typo3.org/54916


Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>