fix(types): fix missing expose() type on setup context

fix #12660

types/test/v3/setup-test.ts

@@ -28,6 +28,9 @@ Vue.extend({
     }
     ctx.emit('foo')
     ctx.slots.default && ctx.slots.default()
+    ctx.expose({
+      a: 123
+    })
   }
 })
 

types/v3-setup-context.d.ts

@@ -33,4 +33,5 @@ export interface SetupContext<E extends EmitsOptions = {}> {
   attrs: Data
   slots: Slots
   emit: EmitFn<E>
+  expose(exposed?: Record<string, any>): void
 }