feat(dev-infra): integrate merge script into ng-dev cli (#37138)

Integrates the merge script into the `ng-dev` CLI. The goal is that
caretakers can run the same command across repositories to merge a pull
request. The command is as followed: `yarn ng-dev pr merge <number>`.

PR Close #37138

dev-infra/utils/console.ts

@@ -0,0 +1,20 @@
+/**
+ * @license
+ * Copyright Google LLC 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
+ */
+
+import {prompt} from 'inquirer';
+
+/** Prompts the user with a confirmation question and a specified message. */
+export async function promptConfirm(message: string, defaultValue = false): Promise<boolean> {
+  return (await prompt<{result: boolean}>({
+           type: 'confirm',
+           name: 'result',
+           message: message,
+           default: defaultValue,
+         }))
+      .result;
+}