docs: Fix prefix typo

Author: joachimvh

documentation/getting-started.md

@@ -404,7 +404,7 @@ Below is an example of the policy that allowed the example above to succeed:
 @prefix odrl: <http://www.w3.org/ns/odrl/2/> .
 
 ex:usagePolicy a odrl:Agreement ;
-                odr:uid ex:usagePolicy ;
+                odrl:uid ex:usagePolicy ;
                 odrl:permission ex:permission .
 ex:permission a odrl:Permission ;
               odrl:action odrl:create ;