Fix typo

Blake Sager · thebadmonkeydev · commit 8c7e486d3eaa · 2019-10-29T11:08:51.000-04:00
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
@@ -18,6 +18,6 @@
 
 * If you have code, by all means, open a pull request!
 
-Thanks again for contirbuting to GraphQL Cache! :tada:
+Thanks again for contributing to GraphQL Cache! :tada:
 
 The StackShare Team
