chore: yarn not install typescript in root folder

Author: 0618

packages/create-amplify/src/amplify_project_creator.ts

@@ -14,7 +14,9 @@ export class AmplifyProjectCreator {
   private readonly defaultDevPackages = [
     '@aws-amplify/backend',
     '@aws-amplify/backend-cli',
-    'typescript@^5.0.0', // TODO: remove this line for yarn since it's installed in amplify/
+    ...(process.env.PACKAGE_MANAGER_EXECUTABLE?.startsWith('yarn')
+      ? []
+      : ['typescript@^5.0.0']), // For yarn, we install typescript at generateInitialProjectFiles();
   ];
 
   private readonly defaultProdPackages = ['aws-amplify'];