add GAIA_PHOT_BP_MEAN_MAG, GAIA_PHOT_RP_MEAN_MAG and their associated errors to GFAs. Also add REF_CAT
add GAIA_PHOT_BP_MEAN_MAG, GAIA_PHOT_RP_MEAN_MAG and their associated errors to GFAs. Also add REF_CAT

desihub/desitarget,desihub/desitarget