Merge pull request #3817 from philips/CONTRIBUTING-is-just-a-dco

fix(CONTRIBUTING): Developer Certificate of Origin w/o Grant

CONTRIBUTING.md

@@ -129,7 +129,7 @@ pass it on as an open-source patch.  The rules are pretty simple: if you
 can certify the below:
 
 ```
-Docker Developer Grant and Certificate of Origin 1.1
+Docker Developer Certificate of Origin 1.1
 
 By making a contribution to the Docker Project ("Project"), I represent and
 warrant that: