select kernel in example notebook

Author: afeld

extras/autograder/submission/example.ipynb

@@ -0,0 +1,16 @@
+{
+ "cells": [],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "python-public-policy",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "name": "python",
+   "version": "3.11.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 2
+}