update link for the first assignment

book/ghfundamentals.ipynb

@@ -17,7 +17,7 @@
     "\n",
     "1. Go through the course's [introduction to Version Control and GitHub](../documents/GitHub.md).\n",
     "1. You need to register on [GitHub](https://github.com/) in order to follow this tutorial. The registration process is described [here](https://www.wikihow.com/Create-an-Account-on-GitHub).\n",
-    "1. When you set up your account use [this link](https://classroom.github.com/a/8DEfC8Tj) to connect to GitHub classroom. Once you follow the link you'll see ![p1](pics_ghf/1.png)\n",
+    "1. When you set up your account use [this link](https://classroom.github.com/a/tXrDNbgp) to connect to GitHub classroom. Once you follow the link you'll see ![p1](pics_ghf/1.png)\n",
     "1. Click `Accept the assignment`. ![p2](pics_ghf/2.png)\n",
     "1. Now you can update the page and see ![p3](pics_ghf/3.png)\n",
     "\n",