Revert eval in DB fix, changing back to 5.38 CV outside referencing behaviour

[tonycoz]

Reverts 386907f06 changing CV outside linking to match 5.38.

This is generally suitable for backporting to 5.40, more complex changes (like making outside a weakref) probably aren't.

• This set of changes requires a perldelta entry, and I need help writing it.

I might add the perldelta later.

This is draft, I plan to add some other TODO tests for the other issues that came up in discussion.

[tonycoz]

Fixes #22547