investigate testNoReplacePersistentCollection (Hibernate 5 and Jackson 3)

[pjfanning]

• turned off when creating Add 3.x versions #190 due to it failing and not being obvious why it only works with Jackson 2
• only fails when Jackson 3 is used and HIbernate 5 (including the Jakarta variant)
• Reproduction of New feature: Strip persistent collections #93 originally

[cowtowncoder]

This is something that might be helped by GenAI coding tools like Claude Code: pointing to repo, failing test, asking to... well, basically "can we fix this", seems to have a chance at helping find solution.

FWTW.

[cowtowncoder]

Looks like failure might be due to "safe" polymorphic type validation, need to configure more forgiving PTV.

[cowtowncoder]

Fixed by copying NoCheckSubTypeValidator from jackson-databind: not sure why H6/H7 did not similarly fail (but they don't).

Will reset versions to 3.0.0-SNAPSHOT, then probably merge.