Fixes shallowRef's return type

Author: simlevesque

src/v3/reactivity/ref.ts

@@ -55,7 +55,7 @@ export type ShallowRef<T = any> = Ref<T> & { [ShallowRefMarker]?: true }
 
 export function shallowRef<T extends object>(
   value: T
-): T extends Ref ? T : ShallowRef<T>
+): [T] extends [Ref] ? T : ShallowRef<T>
 export function shallowRef<T>(value: T): ShallowRef<T>
 export function shallowRef<T = any>(): ShallowRef<T | undefined>
 export function shallowRef(value?: unknown) {