URL validation can disable the Custom URL button for valid URLS

[jacobminer]

Ran into this issue on CI Direct today for a user with an iPhone 12 (iOS 14.1), where entering https://test.ngrok.io would disable the Custom URL button. It seems odd that this would only happen now with iOS 14.1, but I'm also not sure if we need the additional regex for URL validation at all?

[jacobminer]

Our current URL validation is based off this SO answer: https://stackoverflow.com/questions/28079123/how-to-check-validity-of-url-in-swift/36012850#36012850. It's worth noting that other users have had issues with that answers' regex solution, so even if we don't get rid of a regex solution entirely, it's probably worth fixing the issues found there.