update error message

Author: jiashengguo

packages/schema/src/language-server/validator/datamodel-validator.ts

@@ -377,7 +377,7 @@ export default class DataModelValidator implements AstValidator<DataModel> {
                     }
                     accept(
                         'error',
-                        `Field "${refField.name}" of Model "${containingModel.name}" is part of a one-to-one relation and must be marked as @unique or be part of a model-level @@unique attribute`,
+                        `Field "${refField.name}" on model "${containingModel.name}" is part of a one-to-one relation and must be marked as @unique or be part of a model-level @@unique attribute`,
                         { node: refField }
                     );
                 }

packages/schema/tests/schema/validation/datamodel-validation.test.ts

@@ -521,7 +521,7 @@ describe('Data Model Validation Tests', () => {
         `)
         ).toMatchObject(
             errorLike(
-                `Field "aId" of Model "B" is part of a one-to-one relation and must be marked as @unique or be part of a model-level @@unique attribute`
+                `Field "aId" on model "B" is part of a one-to-one relation and must be marked as @unique or be part of a model-level @@unique attribute`
             )
         );