Fix #12303: Evaluating IIIF metadata values dspace.iiif.enabled and iiif.search.enabled correctly

[marsaoua]

Using the double negation (!!) in

dspace-angular/src/app/core/utilities/item-iiif-utils.ts

Line 16 in ffcca7d

return !!item.firstMetadataValue('dspace.iiif.enabled');

converts the value into a strict boolean. In case of dspace.iiif.enabled = false the check will incorrectly treat false as enabled resulting to the error described in DSpace/DSpace#12303

References

Add references/links to any related issues or PRs. These may include:

• Fixes IIIF viewer not evaluating variable correctly DSpace#12303

Description

False/false, null, and undefined are handled safely. Only True\true is matched.

Instructions for Reviewers

Edit an existing or create an item with a metadata value dspace.iiif.enabled = false

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