validationinterface: only send zmq notifications for active

Summary:
This is a partial backport of core#27596
https://github.com/bitcoin/bitcoin/pull/27596/commits/f073917a9e7ba423643dcae0339776470b628f65

Depends on D17890

Test Plan:
ninja all check-all

tested with an actual snapshot and a background chainstate on my dev branch (functional test and mainnet IBD)

Reviewers: #bitcoin_abc, roqqit

Reviewed By: #bitcoin_abc, roqqit

Differential Revision: https://reviews.bitcoinabc.org/D17891