Changes to Minimized public source metadata

api operation id getSourcesStatus was added

added the new optional header request parameter If-None-Match

added the non-success response with the status 304

added the non-success response with the status 429

added the non-success response with the status 503

added the required property _legal_notice to the response with the 200 status

added the required property count to the response with the 200 status

added the required property generated_at to the response with the 200 status

added the required property source_catalog_version to the response with the 200 status

added the required property sources to the response with the 200 status