Changes to CreateEnrichmentVariable creates an enrichment variable that can be used in the enrichment service.

added the new optional request property enrichmentVariable/anyOf[#/components/schemas/protobuf.controlpb.v1.EnrichmentVariable]/policy

added the optional property enrichmentVariable/anyOf[#/components/schemas/protobuf.controlpb.v1.EnrichmentVariable]/policy to the response with the 200 status