Improve exception msg and handling when 'Same Bank' BIC/SWIFT blank

[cparke2]

Users in most countries (see BankUtil.useValidation() for the list of exceptions) can create a "Transfer Same Bank" payment account in Bisq with no BIC/SWIFT code. However, to create an offer using this account type, in most countries (see BankUtil.isBankIdRequired() for these exceptions) the account must have a value in the bankId field, or JAVA will throw a 'null pointer exception', and then the Bisq application will then become unhealthy and hang trying on exit. This fix adds a validation check for that condition and throws a more "friendly" exception which explains the problem, and it happens earlier to keep the app. healthy.

[cparke2]

BEFORE:

AFTER:

[cparke2]

Another thing I wanted to do, but didn't want to "step on someone's toes", was just make the BIC/SWIFT required on the account form for creating the "Transfer Same Bank" payment method. Or, make it use Bank Name rather than BIC for bank matching ("Transfer Specific Banks" works differently already and uses Bank Name for all currencies to match offers). So this pull request represents the minimum: just handle the invalid case more gracefully; hopefully that'll be enough info for the user to fix their problem.

I also opened a discussion on these related account types which raises other issues with this payment method and it's sibling: https://github.com/bisq-network/bisq/discussions/7256