Get actor of interest from scenario metadata and fix metrics

[Adaickalavan]

• Added a specialised metric formula module for Driving SMARTS 2023.1 and 2023.2 benchmark.
• Made all metrics as functions to be minimised, except the overall score which is to be maximised.
• Driving SMARTS 2023.3 benchmark and the metrics module now uses actor_of_interest_re_filter from scenario metadata to identify the lead vehicle.
• Minor fix in regular expression compilation of actor_of_interest_re_filter from scenario metadata.
• Fixed acceleration and jerk computation in comfort metric, by ignoring vehicle position jitters smaller than a threshold.