[SIGMON-352] RB FPA corrections

Context

• task: https://its.cern.ch/jira/browse/SIGMON-352
• lhc-sm-hwc mr: lhc-sm-hwc!109 (merged)

What was done

• The FgcPmSearchModuleMediator queries:
• only the FGC PM dumps from a corresponded 'Safety subsector' (not the whole sector)
• only the FGC PM dumps that contain self in the pm class