Add better handling for web3_clientVersion

[srirambv]

Android version of #19278

Issue posted here to discuss: https://github.com/brave/security/issues/650

But I think BraveWallet/v is an appropriate value instead of asking Infura.

For test plan see the pull request brave/brave-core#12900

[bbondy]

Nothing else needed here, it's already implemented via #19278
If you want to just test this with the dapps release then you can close it and link to it in the test plan of another issue for dapps
I think we probably don't nee this separate issue though.