Add placeholder for what issue a PR resolves

Author: ktoso

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,5 +1,6 @@
 _[One line description of your change]_
 
+
 ### Motivation:
 
 _[Explain here the context, and why you're making that change. What is the problem you're trying to solve.]_
@@ -10,4 +11,5 @@ _[Describe the modifications you've done.]_
 
 ### Result:
 
-_[After your change, what will change.]_
+- Resolves #
+- _[After your change, what will change.]_