fix(custom-elements): stop overriding the provides object of the internal instance

The internal instance of a custom element already inherits the app context’s provides object via the prototype chain, so there’s no need to override it or add extra logic to the `provide` function.

packages/runtime-core/src/apiInject.ts

@@ -23,10 +23,8 @@ export function provide<T, K = InjectionKey<T> | string | number>(
     // own provides object using parent provides object as prototype.
     // this way in `inject` we can simply look up injections from direct
     // parent and let the prototype chain do the work.
-    // #13212, custom elements inherit the provides object from appContext
-    const parentProvides = currentInstance.ce
-      ? currentInstance.appContext.provides
-      : currentInstance.parent && currentInstance.parent.provides
+    const parentProvides =
+      currentInstance.parent && currentInstance.parent.provides
     if (parentProvides === provides) {
       provides = currentInstance.provides = Object.create(parentProvides)
     }

packages/runtime-dom/src/apiCustomElement.ts

@@ -316,7 +316,6 @@ export class VueElement
   private _setParent(parent = this._parent) {
     if (parent) {
       this._instance!.parent = parent._instance
-      this._instance!.provides = this._instance!.appContext.provides
       this._inheritParentContext(parent)
     }
   }