cubicweb-saem_ref #15823547 add oaipmh metadata prefix to export record as eac [validation pending]

for arkheia export

prioritynormal
typeenhancement
done in0.13.0
load left0.000
closed by#b3518a580cca [eac/oai] Expose authority record using an eac metadata prefix
patch[eac/oai] Expose authority record using an eac metadata prefix [applied]