Add comma

guides/index.rst

@@ -15,7 +15,7 @@ a step by step :ref:`contribution guide <gsoc-contribution-guide>`.
     :fas:`graduation-cap` **Student Guide**
     ^^^^
 
-    If you want to increase your chances of being accepted into (and succeed during) Google Summer of Code we strongly 
+    If you want to increase your chances of being accepted into (and succeed during) Google Summer of Code, we strongly 
     encourage you to read this guide! It is particularly helpful for tips on writing a good project proposal and how 
     potential contributors should interact with the communities they are interested in working with during the program.