log RPC arguments for testnets #2
Description
This PR bitcoin#16365 attempted to log only non-secret RPC arguments for all networks (including mainnet), and that turned out to be difficult, and therefore not a popular idea. But logging them for just the testnets (testnet, signet) would be very useful, especially for understanding why tests are failing (or how they work).
So probably create a new PR that does that (would be quite a bit different, so probably best not to resurrect this closed PR).