Display error if user tries to send with priority fee without funds to pay for it #780
Description
Describe the solution you'd like and the expected behavior
If a user tries to make a transaction with a priority fee, but the user wallet holds no funds for said fee, the transaction dialogue closes on confirmation and nothing appears to happen.
For NEO blockchain transactions: Users should get a prompt to send without a priority fee if they don't have the funds (if a priority fee is configured).
For ETH transactions: Users should get an error.