Implement "PUT /objects/{object_id}/access/{access_id}"

[uniqueg]

Description

Analogous to #24, but for adding or updating an access method with a user-defined identifier.

Proposed solution

• Add a PUT /objects/{object_id}/access/{access_id} endpoint to the DRS-Filer custom OpenAPI specification here; an example for a PUT endpoint definition can be found in the TRS-Filer repository
• Add a controller for the endpoint; make sure that it is compatible with the solution to Implement "POST /objects/{object_id}/access" #25, if already resolved; an example for a controller that is used for both POSTing and PUTting resources can be found in the TRS-Filer repository
• Add/update the necessary unit tests