Fix form validation

[haraldox]

Description

fixes form validation error messages Franz-wide

Motivation and Context

when submitting during signup as well as when adding services without field values, no error message appears

How Has This Been Tested?

all screens with forms tested manually

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist:

• My code follows the code style of this project (run $ yarn lint).