OF: Only force a diff if it's a merge not from an apache repo
OF: Only force a diff if it's a merge not from an apache repo

This should hopefully address INFRA-17931
sebbASF/infrastructure-puppet,apache/infrastructure-puppet,apache/infrastructure-puppet,apache/infrastructure-puppet,apache/infrastructure-puppet,sebbASF/infrastructure-puppet,apache/infrastructure-puppet,apache/infrastructure-puppet,apache/infrastructure-puppet,sebbASF/infrastructure-puppet,sebbASF/infrastructure-puppet,sebbASF/infrastructure-puppet,sebbASF/infrastructure-puppet,sebbASF/infrastructure-puppet,sebbASF/infrastructure-puppet