adds custom URL to ignored fields for versioning, as the custom URL n…

[olli-gold]

…eeds to be unique and should not be transferred into the new version

Description

The custom URL in DSpace-CRIS must be unique and the same address cannot be used for multiple items. The versioning system of DSpace transfers all fields to the new version of the item, except for some configurable ignored fields. Thus the default configuration for versioning should contain the cris.customurl field as an ignored field.

Instructions for Reviewers

None (it's just a very small configuration change).

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