Fix typo (vsouza#1919)

Author: Miguel Araújo

Dangerfile

@@ -16,7 +16,7 @@ results = File.read 'ab-results-README.md-markdown-table.json'
 j = JSON.parse results
 if j['error']==true
   m = j['title']
-  m << ', a project collaborator will take care of these, thanks: )'
+  m << ', a project collaborator will take care of these, thanks :)'
   warn m
   markdown j['message']
 end