Merge pull request #1804 from cisagov/nl/1586-zip-code-error-message

Issue #1586 - Use one error message for zip code validation or when a zip code field is empty

src/registrar/forms/application_wizard.py

@@ -284,6 +284,7 @@ class OrganizationContactForm(RegistrarForm):
                 message="Enter a zip code in the form of 12345 or 12345-6789.",
             )
         ],
+        error_messages={"required": ("Enter a zip code in the form of 12345 or 12345-6789.")},
     )
     urbanization = forms.CharField(
         required=False,