enable fsr auto config
In !4739 (merged) the writing of FSR at an earlier stage than sprucing for MC is already enabled. This MR goes with the Integrationtest LHCbIntegrationTests!92 that checks the correct propagation of keys and options for MC from HLT1 to Spruce output.
Quick summary of the changes:
- enhance the use of auto config
- adjustments to the reading of fsr in lbexec so it works for merged as well as not merged file (application options can be read from 'input' key or top level fsr)
- add two small unit tests to ensure when keys/options are set to be written into the fsr they actually appear
Edited by Ellinor Eckstein