pseudomerge of TrigHLTMonitoring packages from rel 21 to master, ATR-18999

Pseudomerge of the TrigHLTMonitoring packages from rel 21 to master, as described in ATR-18999

Command to run the pseudomerge:
git-package-pseudomerge.py --packages Trigger/TrigMonitoring/TrigHLTMonitoring --source upstream/21.0-TrigMC --target upstream/master --stage 1

The following files are affected:

Files where the rel 21.0 version has been kept unaltered:
Trigger/TrigMonitoring/TrigHLTMonitoring/python/HLTMonFlags.py (new)
Trigger/TrigMonitoring/TrigHLTMonitoring/python/PackagesToInterrogate.py (new)
Trigger/TrigMonitoring/TrigHLTMonitoring/python/ToolInterrogator.py (new)
Trigger/TrigMonitoring/TrigHLTMonitoring/share/runMaM.py (new)
Trigger/TrigMonitoring/TrigHLTMonitoring/java/GUI/TrigMaMGUI.java
Trigger/TrigMonitoring/TrigHLTMonitoring/java/TrigMaMGUI_P1.sh
Trigger/TrigMonitoring/TrigHLTMonitoring/java/TrigMaMGUI_TRIGGERDBREPR.sh
Trigger/TrigMonitoring/TrigHLTMonitoring/python/HLTMonTriggerList.py
Trigger/TrigMonitoring/TrigHLTMonitoring/python/MenuAwareMonitoring.py
Trigger/TrigMonitoring/TrigHLTMonitoring/python/MenuAwareMonitoringStandalone.py
Trigger/TrigMonitoring/TrigHLTMonitoring/python/OracleInterface.py
Trigger/TrigMonitoring/TrigHLTMonitoring/python/scripts/MCKtoCOOLmanual.py
Trigger/TrigMonitoring/TrigHLTMonitoring/run/TrigHLTMon_tf.py
Trigger/TrigMonitoring/TrigHLTMonitoring/share/HLTMonitoring_topOptions.py
Trigger/TrigMonitoring/TrigHLTMonitoring/share/TrigHLTMonCommon_jobOptions.py
Trigger/TrigMonitoring/TrigHLTMonitoring/share/addMonTools.py
Trigger/TrigMonitoring/TrigHLTMonitoring/share/skeleton.HLTMon_tf.py

Files where master has been kept unaltered:
Trigger/TrigMonitoring/TrigHLTMonitoring/CMakeLists.txt
Trigger/TrigMonitoring/TrigHLTMonitoring/src/IHLTMonTool.cxx

Deleted file:
Trigger/TrigMonitoring/TrigHLTMonitoring/cmt/requirements

File where master has been used with alterations:
Trigger/TrigMonitoring/TrigHLTMonitoring/src/HLTMonTool.cxx
where the lines

if (chain.find("gsc") != std::string::npos) { 
 continue;
 }

have been removed to match the jet trigger update from the pseudomerge of https://gitlab.cern.ch/atlas/athenaprivate1/merge_requests/16753