There's a new dev branch for qtqa, so we can re-enable CMake builds
of qtqa using that branch, without breaking builds of other branches.
This reverts commit 33e8275ee5.
Task-number: QTBUG-84233
Change-Id: I1e4ca39717768303eca8435d175aa562fcd6f0f5
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>