Reference run sequence with BE SMOG2 minimum bias

This MR adds a sequence for the pp reference run:

hlt1_pp_ref_forward_then_matching_HeD_BEMB

This sequence is similar to the He/D2 reference run sequence, but it includes an open beam-empty SMOG2 minimum bias line. This will roughly double the SMOG2 minimum bias rate during pHe and pD data taking, allowing us to reach our targeted yields faster. In addition, beam-empty events will be smaller than BB, so this should decrease the overall disk volume for the pp reference run by a few 10s of TB.

In addition, this MR also loosens the prescale for the SMOG2 luminosity line in the new pp reference run sequence.