Refactor application team routes

- pulling out helper functions for constructing forms
- return 400 for form validation errors
- "Yes" appears green on the read only version

atst/forms/team.py

@@ -26,7 +26,7 @@ class PermissionsForm(FlaskForm):
     )
     perms_del_env = SelectField(
         choices=[
-            ("View only", "No"),
+            (PermissionSets.VIEW_APPLICATION, "No"),
             (PermissionSets.DELETE_APPLICATION_ENVIRONMENTS, "Yes"),
         ]
     )
@@ -49,13 +49,6 @@ class MemberForm(FlaskForm):
     environment_roles = FieldList(FormField(EnvironmentForm))
     permission_sets = FormField(PermissionsForm)
 
-    @property
-    def data(self):
-        _data = super().data
-        _data.pop("csrf_token", None)
-
-        return _data
-
 
 class TeamForm(BaseForm):
     members = FieldList(FormField(MemberForm))