Draft: TrigConfStorage+TrigConfigSvc: fix parsing of DB alias and use LB for query
Two independent fixes:
- The "ConfigSource" string in COOL changed for Run-3 and now uses a semicolon as delimiter (see ATR-21550). Adjust the code and add a unit test for Run-2.
- Use the lumiblock number when querying the trigger configuration from COOL. This might help reducing the changes of retrieving stale values from Frontier (ATR-26381).