LC uses online valid registered PFSs for presences even if they're operating on another network, causing offline presence responses

[andrevmatos]

Steps to Reproduce

1. stable/v2 SDK with PFS in auto mode (e.g. hosted instance at https://lightclient.raiden.network)
2. Go to goerli (which uses v0.40 goerli_unstable contracts)
3. It'll pick up valid (on registry deposit) PFSs, and when trying to check availability of a peer, use the first registered and online one, even if it's not operating on the same TokenNetworkRegistry
4. Any registered PFS is offline or not replying properly, it's bypassed; but if the PFS is in fact online, it'll be used for presence; if it happens that this PFS is registered, online but working on a different network, it'll always reply that peers are offline

Notice that this error is caused by infrastructure misconfiguration, but the client must do better to identify this case and find valid services nonetheless.

Expected Result

• Only a PFS which is registered, valid, online and operating on the same TNR as the node is picked for requests (including presence and route)

Actual Result

• PFSs which are registered, valid and online, but not on the same TNR, may be picked up, and will prevent the node from getting consistent responses, instead getting always-offline-peer replies or no route found;

Additional Infos (Optional)

Current stable (latest v2.1.0) and master (arbitrum development branch) are affected

[andrevmatos]

Fixed in #3101