Create UI tests for AccountBalanceCard widget

[ethanwlee]

• using the existing test suite as an example, create UI tests to stress-test the AccountBalanceCard widget
• currently, the AccountBalanceCard widget is only responsible for displaying the account total and account currency which is fetched from the AccountBalanceNotifier

[victoreronmosele]

.take

[github-actions]

Thanks for taking this issue! Let us know if you have any questions!

[blackgirlbytes]

@victoreronmosele hey there! how's this issue going for you? Let us know if you need any help

[victoreronmosele]

@blackgirlbytes, hi!

The issue is going well, thanks.

I plan to create a PR very soon.

[victoreronmosele]

The PR is up now.

[blackgirlbytes]

ah, thank you! We'll have @ethan-tbd check this when he gets a chance! Appreciate the contribution @victoreronmosele