[avalanche] bump the misbehavior for oversized AVAPOLL messages

Summary:
20 was an arbitrary value. If a node does not format its messages correctly it will get disconnected soon anyway, so don't give it 4 more chances and just disconnect it immediately.

Depends on D18016

Test Plan: ninja all check-all

Reviewers: #bitcoin_abc, Fabien

Reviewed By: #bitcoin_abc, Fabien

Subscribers: Fabien

Differential Revision: https://reviews.bitcoinabc.org/D18017