NSW Trigger Simulation - sTGC strip cluster tool second update

A follow-up of !50178 (merged), to fix some points still left:

• Simplified algorithm workflow: made pad cache local (potentially fixing segmentation faults when running in MT mode) and removed enum structure
• declareProperty instances replaced by Gaudi::Property ones, in order to change them from the main steering python, if needed
• Added a check to prevent the sTGC trigger code accessing SDO container when running on data
• Clean-up of variables/functions/comments not used, redundant or not useful to understand the code
• Used range-based for loops
• Improved code readability: fixed alignment and indentations

./cc-ing @iodice @rosati @vadamico @ztarem