You can currently subset (query for) specifications by passing a metadata term dictionary to the Jobs.specs.subset() method. This kind of query was intended to be permissive and just match any specification that could apply given a Job's metadata. This meant that if the Job metadata had an extra term that the Specification does not filter by, that specification would still be applicable to the job.
DM-12253, Simon Krughoff needs to subset specifications by an exact match to the input metadata query terms. This means that if the queried metadata has terms not present in a Specification's metadata, that specification does not match.
This ticket is to implement that alternative query pattern.