In OpenAIRE/oai_datacite export, when user doesn't enter an Other Identifier Agency, default alternateIdentifierType to ":unav"

[jggautier]

Overview of the Feature Request

When the user adds an Other Identifier but does not enter an Agency, the OpenAIRE/oai_datacite export should default alternateIdentifierType to :unav, as the DataCite/Datacite export already does. Currently, the OpenAIRE/oai_datacite export doesn't include alternateIdentifierType at all in this case.

This issue is part of a larger effort to align both metadata exports, described in #11916.

What kind of user is the feature intended for?

API User, Superuser, and Sysadmin

What inspired the request?

This is part of a larger effort to align the OpenAIRE/oai_datacite and DataCite/Datacite metadata exports. There is more context at #11916.

What existing behavior do you want changed?

Currently, when the user adds an Other Identifier but does not choose an Agency, the DataCite/Datacite export defaults alternateIdentifierType to :unav. For example:

<alternateIdentifier
    alternateIdentifierType=":unav">https://nogagencyvalue.org/1234
</alternateIdentifier>

The OpenAIRE/oai_datacite export doesn't include alternateIdentifierType all all in this case.

The OpenAIRE/oai_datacite export should be changed to default alternateIdentifierType to :unav when the user doens't enter anything in the Agency field, matching the behavior of the DataCite/Datacite export.

Any open or closed issues related to this feature request?

#11916