Update DOI service for handling existing DOIs acceptance criteria per #175

[jordanpadams]

Engineering Details

Follow-on to #175, this acceptance criteria needs to be addressed. Per these slides, DataCite allows a user to create their own custom DOI identifier if the DOI does not exist in the system.

We want to make sure this does not happen. So we want to check our DB if that DOI exists, if not, then we should not allow an update to the metadata (it most likely means someone changed the DOI prior to submitting the update).

• check if the code already does this check
• implement the check if does not exist

Acceptance Criteria

Given a DOI that does not exist
When I perform an attempted update of that DOI metadata
Then I expect to receive an error message that DOI does not exist

[jordanpadams]

Per discussions today, this is mostly prevented by the DOI UI. A user could create their own DOI, but the system will catch if it a new DOI for the same LIDVID, so that is sufficient details.

the only way someone could misuse this is if they are using the service directly, which is not planned.

closing as wontfix