[COOK-1087] Update the CONTRIBUTING file to fix a minor typo
[COOK-1087] Update the CONTRIBUTING file to fix a minor typo

chef-cookbooks/stompserver,cookbooks/oc-stompserver,opscode-cookbooks/stompserver,chef-cookbooks/stompserver,opscode-cookbooks/stompserver,opscode-cookbooks/stompserver,chef-cookbooks/stompserver