Document the difference of eth_sign and personal_sign

[sbc64]

https://github.com/WalletConnect/walletconnect-monorepo/issues/1395

The above issue is a trap that a lot of developers fall for. It would save us a lot of support time if we can make this gotcha very clear in the docs.

[hackyguru]

Thanks for the suggestion @sbc64 definitely agree to your point. I'll fix this issue by tomorrow and update here :)

[sumer-meso]

any updates?