JER file naming convention for Run3 breaks FactorizedJetCorrector/CorrectedJetsFactory

[miozdemi]

The following is similar to a previous issue (#1111).

I was looking into the implementation of the Jet/Met Factories for my analysis and came across something interesting. While the JEC names from the JECDatabase (https://github.com/cms-jet/JECDatabase/tree/master) (for example Summer23Prompt23_V1_MC_L1FastJet_AK4PFPuppi) don't have any problems when read in, the JER names from the JRDatabase (https://github.com/cms-jet/JRDatabase/tree/master) (for example Summer23Prompt23_RunC1234_JRV1_MC_SF_AK4PFPuppi) return an exception Corrector name is not properly formatted!
When I looked into the JetResolution.py and FactorizedJetCorrector.py I noticed a difference here (https://github.com/scikit-hep/coffea/blob/v0.7.22/coffea/jetmet_tools/FactorizedJetCorrector.py#L76) and here (https://github.com/scikit-hep/coffea/blob/v0.7.22/coffea/jetmet_tools/JetResolution.py#L69) for both coffea 0.7.x and 2024.

One can reproduce the exception with the example code from the jet-hats exercise 2.4 here (https://github.com/FNALLPC/jets-hats/blob/main/notebooks/Jet_Energy_Corrections.ipynb) and just insert the two files mentioned above.

I think like in #1111 the additional underscore breaks the naming convention. Currently I am manually removing the era string by hand (_RunC1234).