[checkers] remove trailing '\n' in checker messages
[checkers] remove trailing '\n' in checker messages

gebi/multipath-tools,unakatsuo/multipath-tools,unakatsuo/multipath-tools,vijaychauhan/multipath-tools,grzn/multipath-tools-explained,unakatsuo/multipath-tools,grzn/multipath-tools-explained,vijaychauhan/multipath-tools