doc(PULL_REQUEST_TEMPLATE): fix commit style guideline link

Author: Aaron Schlesinger

.github/PULL_REQUEST_TEMPLATE

@@ -47,4 +47,4 @@ Please make sure the below checklist is complete.
 
 - [ ] Your pull request is concise and to the point (make another PR for refactoring nearby code)
 - [ ] Your commits are squashed into logical units of work
-- [ ] Your commits follow the [commit style guidelines](http://docs.deis.io/en/latest/contributing/standards.html#commit-style)
+- [ ] Your commits follow the [commit style guidelines](http://docs.deis.io/en/latest/contributing/standards/#commit-style-guide)