Typo in error string

[giorgionocera]

There is a typo in the error string returned when an error occurs while getting chain id:

cosmos-go-wallet/client/client.go

Line 101 in f9a5a35

return "", fmt.Errorf("error while gestting chain id: %s", err)

Here, "gestting" should be "getting".

I'll provide a PR for this.