Avoid indefinite connection attempts

[madadam]

trafficstars

Currently we try to connect to a peer for as long as they are advertised to us via one of the discovery mechanism (explicitly provided by the user, local discovery, DHT, PEX). There are some cases where a connection is impossible however, for example there might be too restrictive NAT or we might be on different subnets, and so on. Ideally we should be able to detect this and abort the connection attempts in those cases.

[IvanaBlzvc]

https://redmine.equalit.ie/issues/31634