Add ever changing property to ignore list of confTool --diff
The confTool --diff option reports always about this difference:
Component PerfMonMTSvc may differ
wallTimeOffset = 1677740000000.0 vs 1677750000000.0 <<
but all are suppressed by renaming/known differences/...
even if "--ignoreIrrelevant" was enabled. Now, this ever changing property is added to the ignore list.