chore: using symbol as provide key (#8260)

src/composables/use-link-field.ts

@@ -1,8 +1,8 @@
 import { ComponentInstance } from '../utils';
 import { watch, inject } from 'vue';
 
-export const FORM_KEY = 'vanForm';
-export const FIELD_KEY = 'vanField';
+export const FORM_KEY = Symbol('Form');
+export const FIELD_KEY = Symbol('Field');
 
 export function useLinkField(getValue: () => unknown) {
   const field = inject(FIELD_KEY, null) as ComponentInstance | null;