Merge topic 'autogen-timestamp-per-config'

bac468ddfd AutoGen: Fix regression in timestamps on multi-config generators
c3f0825d3c Tests/RunCMake/Autogen: Factor out test setup
9654835b4f Tests/RunCMake/Autogen: Add expect_n_times() function

Acked-by: Kitware Robot <kwrobot@kitware.com>
Tested-by: buildbot <buildbot@kitware.com>
Merge-request: !8840