Sync providers' error messages UI inconsistency

[Jan Six]

Two issues with Sync provides that we should solve:

• When creating or editing sync providers, all required fields should be required and cause Save to not be able to submit (mark fields as required for the form)
• Required fields should not show the browser-native validation, but rather show our own ErroValidation styled error string.

CleanShot.2024-06-14.at.16.09.27.mp4