Develop a CLI tool to allow initial filling with data for testing purposes.

• Add non-production endpoint to the mod-source-record-storage to allow the addition of MARC records for testing purposes. mod-source-record-storage must have a dedicated stub snapshot to store such records.
• The endpoint should consume a bunch of valid MARC records and store them linked to that snapshot. No additional validation or parsing is needed.
• The endpoint is available (does not return an error) in case there is an environment configuration entry for that. Otherwise the endpoint returns an error. Use configuration provided in https://issues.folio.org/browse/FOLIO-1616

Acceptance criteria

• working endpoint in mod-source-record-storage
• examples of CURL or POSTMAN collection demonstrating how to use it on the FOLIO WIKI page