Add balance command

[jrchatruc]

What 💻

• Add npx zksync-cli wallet balance command to check ETH balance of the specified address

Why ✋

• Seeing ETH balance might be useful during the development

Evidence 📷

[JackHamer09]

Should we also ask for which token to get balance to? ETH or ERC20
And then if ERC20 is selected we also ask for address of the token.
Would be useful to have something like that :)
Not required for this PR tho..

[jrchatruc]

Should we also ask for which token to get balance to? ETH or ERC20 And then if ERC20 is selected we also ask for address of the token. Would be useful to have something like that :) Not required for this PR tho..

That would be very useful indeed, we'll add it on a subsquent PR!

[jrchatruc]

Addressed all the commends above here aef66ef and here 2e88921. In regards to this

For now there is no L1 features.
So we should either not mention L1 and just say Manage zkSync wallet related features
or
Add possibility to choose L1 network in the list.

For now I just changed the description to not mention L1, we might add L1 features in the future.