fix(types): allow attaching unknown options to defined component

fix #12742

Author: yyx990803

Diff for: types/test/v3/define-component-test.tsx

@@ -1165,3 +1165,7 @@ defineComponent({
     return h('div', {}, [...this.$slots.default!])
   }
 })
+
+// #12742 allow attaching custom properties (consistent with v3)
+const Foo = defineComponent({})
+Foo.foobar = 123

Diff for: types/v3-component-options.d.ts

@@ -88,6 +88,9 @@ export interface ComponentOptionsBase<
       'data' | 'computed' | 'methods' | 'setup' | 'props' | 'mixins' | 'extends'
     >,
     ComponentCustomOptions {
+  // allow any options
+  [key: string]: any
+
   // rewrite options api types
   data?: (
     this: CreateComponentPublicInstance<Props, {}, {}, {}, M, Mixin, Extends>,