Move to more modern Starterkit Bs -> Jpsi Phi line in HltEfficiencyChecker examples

Goes with Moore!2259 (merged).

The legacy Hlt2BsToJpsiPhi is based on LoKi and therefore being removed, so this MR mainly updates to use the more modern Starterkit version of this line.

Addresses one half of Moore#469 (closed) (Moore!2248 (merged) will do the rest), and closes #38 (closed).