Drop SlimmingHelper legacy config

Dropped dependence to legacy RecExConfig in SlimmingHelper + pass the CA flags as flags instead of ConfigFlags.

All derivation configs configuring the SlimmingHelper are updated accordingly, changing as well flags into ConfigFlags.

As this is Legacy Config Removal aimed at 24.0 but backport a few derivation configs impacted by this update from main to make sweep easier. In particular:

• the BTagging_AntiKt4UFOCSSK collection added with !69459 (merged) is also added
• TEST7.py is added following !69413 (merged)
• include updates to PHYS.py following !68278 (merged)