If we reuse the same port when disconnecting and establishing connections
again, we might hit this scenario:
- disconnection is done on python side for P2PConnection
- disconnection is not complete on c++ side for TestNode
- we're trying to establish a new connection on same port again
Prevent this scenario from happening by ensuring disconnection on c++
side for TestNode as well.
The test requires that limited nodes are not peered with when
the node's system time exceeds ~ 24h of the node's chaintip
timestamp, as per PeerManagerImpl::GetDesirableServiceFlags.
By patching this test to modify the timestamp of the chaintip as
opposed to mocking the node's system time, we make it resilient
to future commits where the node raises a warning if it detects
its system time is too much out of sync with its outbound peers.
See https://github.com/bitcoin/bitcoin/pull/29623