Updated doc

Author: ogulcanturan

docs/v1/upgrading/toc.yml

@@ -2,6 +2,8 @@
   href: index.md
   expanded: true
   items:
+    - name: From v1.1 to v1.2
+      href: v1.1-to-v1.2.md
     - name: From v1.0 to v1.1
       href: v1.0-to-v1.1.md