The bug
Programmer Art generally does not duplicate model files, however one appears to have snuck in recently:
block/dragon_egg.json
This is completely visually identical to the normal dragon egg model, besides some broken texture mapping and an incorrectly-sized cuboid. It can therefore safely be deleted without sacrificing anything of note.
How to fix
Delete this model file from the Programmer Art resource pack.
Linked issues
relates to 3
Comments 1

Thank you for your report!
After consideration, the issue is being closed as Working as Intended.
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