Draft: TrigBtagEmulationTool: Add BJet trigger emulation tool

Add the TrigBtagEmulationTool to r22 in the Trigger/TrigEmulation directory. This tool was available for r21 but needed to be rewritten for run3 (ATR-22285). This is the result of that effort. It does not touch anything except adding the tool to the newly created Trigger/TrigEmulation directory.

Tagging @dguest and @cpollard as bjet trigger group conveners and previous maintainer of the tool @cvarni.