Run L1T emulation for Fast Simulation bugfix 730

This fixes a bug when running Fast Simulation in postLS1 scenario, where new L1T emulation was not run but inputs were expected downstream.  This bug fix causes new L1T emulation to be run in all scenarios where legacy GCT emulation was run, if postLS1 customization is made.  It also sets the l1extra producer to use simulated or unpacked digis based on context.
Please remove up to line 22 (remnant of #6584)