Invalid requests are still counted for the IP daily limit

[sakibarifin]

If a user inputs data in wrong format to the faucet form, it assumes the user has received faucet funds even though that is false. So, the faucet forces people to wait 24 hours if they make a single typo and enter the address incorrectly. It neither sends the funds nor allows the user to submit the form correctly again to receive funds as the timer is triggered even if the user didn't receive any testnet tokens.

• same issue for when testnet account creation fails

This issue can be fixed by adding input validation mentioned in #259