#6094 Prevent creating a custom field with an existing name (#6100)

Fixes #6094 
Description: Added logic inside SettingsObjectNewFieldStep2.tsx to
prevent form submission
Current Behaviours:
<img width="947" alt="Screenshot 2024-07-03 at 1 45 31 PM"
src="https://github.com/twentyhq/twenty/assets/95612797/bef54bc4-fc83-48f3-894a-34445ec64723">

---------

Co-authored-by: Marie Stoppa <marie.stoppa@essec.edu>

packages/twenty-front/src/pages/settings/data-model/SettingsObjectFieldEdit.tsx

@@ -38,7 +38,7 @@ import { FieldMetadataType } from '~/generated-metadata/graphql';
 import { isDefined } from '~/utils/isDefined';
 
 type SettingsDataModelFieldEditFormValues = z.infer<
-  typeof settingsFieldFormSchema
+  ReturnType<typeof settingsFieldFormSchema>
 >;
 
 const StyledSettingsObjectFieldTypeSelect = styled(
@@ -93,7 +93,7 @@ export const SettingsObjectFieldEdit = () => {
 
   const formConfig = useForm<SettingsDataModelFieldEditFormValues>({
     mode: 'onTouched',
-    resolver: zodResolver(settingsFieldFormSchema),
+    resolver: zodResolver(settingsFieldFormSchema()),
   });
 
   useEffect(() => {