Added system test for PoldiPeakSearch
Added another peak search reference
Adapted SystemTest to new PoldiPeakSearch output workspace
Adjusted PoldiPeakSearch systemtest

New intensity and background estimations lead to different intensity guesses,
so they are not comparable anymore.

In combination with new background estimation, some small peaks (which usually are no peaks) will not be found,
or different ones will be discovered.
Added comment to explain test
Refs #9432. Added system test for PoldiPeakSearch
Refs #9432. Added system test for PoldiFitPeaks1D
Merge branch 'feature/9432_system_tests_poldi_peak_search_and_fit' into develop