Test direct and mediated transfers on Arbitrum

[taleldayekh]

Description

Acceptance criteria

Tasks

• [ ]

[andrevmatos]

I did test transfers after #2913 , and all works well. Only issue was when using dApp, on which Metamask has the tendency of caching the blockNumber, and therefore on fast blockchains as Arbitrum (which can produce batches of blocks instantly and/or on quick bursts), it can be outdated for some seconds, making transfers be dropped on the receiving side as it'd already be inside the danger zone. The fix is to either (or both) fix this Metamask block caching, or calculate reasonable timeout parameters considering the fast pace of blocks production, specially for transfer timeout (blocks margin before danger zone), withdraws and settle timeouts.
But this should be just a matter of tweaking the parameters, client and logic should be solid, therefore I'm considering this issue as done.