Introduced default TrkVKalVrtFitterCfg

Introduce default CA config for TrkVKalVrtFitter + update name of existing config method to SecVx_TrkVKalVrtFitterCfg for clarification.

For @abarton as master RC, I will manually prepare a sweep MR to master as there are some extra configs there which need a bit of care.

FYI @kostyuk