style: add file header (angular#28871)

PR Close angular#28871

Author: gregmagolan

tools/npm/@angular_bazel/index.js

@@ -1 +1,14 @@
-throw new Error('should never be run');
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+/**
+ * @fileoverview This files is only here so that @npm//@angular/bazel/bin:ngc-wrapped
+ * is a valid target as it is part of `esm5_outputs_aspect` in /packages/bazel/src/esm5.bzl
+ * TODO(gregmagolan): fix esm5_outputs_aspect so that this is not required
+ */
+
+throw new Error('should never be run');