TrigT2CaloEgamma: further Run-2 package cleanup
- delete unused python classes and files
- fix some include guards
- fix link dependencies
- enable thread checker for
EgammaAllFex
Also delete some commented code in TrigMissingETHypoConfigMT.py
that gives false positives when searching for obsolete trigger code with git grep
.
Relates to ATR-22796.