Fixed broken link to CONTRIBUTING.md

.github/ISSUE_TEMPLATE.md

@@ -1,6 +1,6 @@
 <!--
   Please read the contributing guidelines before opening an issue:
-  https://github.com/freeCodeCamp/devdocs/blob/master/CONTRIBUTING.md
+  https://github.com/freeCodeCamp/devdocs/blob/master/.github/CONTRIBUTING.md
 
   To request a new documentation, or an update of an existing documentation, go here:
   https://trello.com/b/6BmTulfx/devdocs-documentation