build(deps): upgrade to TypeScript 4

packages/runtime-core/src/apiInject.ts

@@ -37,7 +37,7 @@ export function inject(
   const instance = currentInstance || currentRenderingInstance
   if (instance) {
     const provides = instance.provides
-    if (key in provides) {
+    if ((key as string | symbol) in provides) {
       // TS doesn't allow symbol as index type
       return provides[key as string]
     } else if (arguments.length > 1) {