[backport#15644] Interrupt orphan processing after every transaction

Summary:
This makes orphan processing work like handling getdata messages:
After every actual transaction validation attempt, interrupt
processing to deal with messages arriving from other peers.

Depends on D6217

Concludes backport of Core PR15644

Test Plan:

ninja check-all

Reviewers: #bitcoin_abc, deadalnix

Reviewed By: #bitcoin_abc, deadalnix

Subscribers: deadalnix

Differential Revision: https://reviews.bitcoinabc.org/D6235