Remove PS:Online label and handling

We have wanted to phase out this label for a while as it was used for all sorts of things. In principle this is a pretty straightforward change, but there are a few details to discuss.

It's not 100% clear what to do with a few specific chains.

• HLT_2j20_mb_afprec_afpdijet_L1RD0_FILLED, HLT_2j120_mb_afprec_afpdijet_L1AFP_A_AND_C, HLT_2j175_mb_afprec_afpdijet_L1AFP_A_AND_C --> Left alone (but no AFP sim?)
• muCombTag --> kept in PhysicsP1 as L1_MU20VFC not available in MC
• j0_perf --> Reenabled unconditionally. Historically considered 'too expensive' for MC, but we run j15_(pf_ftf_)L1RD0_FILLED which overlaps 100% in CPU so there is probably no good reason to exclude, and j0_perf is slightly better for calibration and emulation.
• Various Main streamers --> exclude all except for HLT_noalg_L1All
• Beamspot allTE --> simply remove from Dev now that the switch to FS FTF tracking is done

Ideally we thought there should be no chains in the PhysicsP1_pp menu, but some of the streamers need to stay there because their L1 items are removed from the MC menu, hence they can't be in Physics_pp.

FYI @mark, @sshaw, @tamartin, @lidiaz, @astruebi

• Check if the menu prescale sets are being respected