OpenSeadragon viewer does not display for Anonymous on Drupal 9

[alxp]

PR: Islandora/openseadragon#35

Steps to reproduce:

On Fresh Drupal 9 Islandora install (using playbook in our case)

1. Create a Repository Object and select Image for the Model and Resource Type, and 2. OpenSeadragon for the display hint.
2. Add a Media of type Image.
3. Log out and view the object node.

Expected Behaviour

The user should see the OpenSeadragon viewer.

Actual behaviour

No viewer is displayed.

The drupal/core library is now explicitly required if the Drupal object is accessed by a module when user is Anonymous.

[seth-shaw-unlv]

Resolved with Islandora/openseadragon@0fd1218.