6629d1d0f8 test: improve robustness of connect_nodes() (furszy)
Pull request description:
Decoupled from #27837 because this can help other too, found it investigating a CI failure https://cirrus-ci.com/task/5805115213348864?logs=ci#L3200.
The `connect_nodes` function in the test framework relies on a stable number of peer
connections to verify that the new connection between the nodes is successfully established.
This approach is fragile, as any of the peers involved in the process can drop, lose, or
create a connection at any step, causing subsequent `wait_until` checks to stall indefinitely
even when the peers in question were connected successfully.
This commit improves the situation by using the nodes' subversion and the connection
direction (inbound/outbound) to identify the exact peer connection and perform the
checks exclusively on it.
ACKs for top commit:
stratospher:
reACK 6629d1d.
achow101:
ACK 6629d1d0f8
maflcko:
utACK 6629d1d0f8
AngusP:
re-ACK 6629d1d0f8
Tree-SHA512: 5f345c0ce49ea81b643e97c5cffd133e182838752c27592fcdeac14ad10919fb4b7ff38e289e42a7c3c638a170bd0d0b7a9cd493898997a2082a7b7ceef4aeeb
e163d864d3