7183753: [TEST] Some colon in the diff for this test

Summary: Reference output file contains extra colon
Reviewed-by: sspitsyn, mgronlun

test/sun/tools/jcmd/help_help.out

 help
 For more information about a specific command use 'help <command>'. With no argument this will show a list of available commands. 'help all' will show help for all commands.
 
-Impact: Low: 
+Impact: Low 
 
 Syntax : help [options] [<command name>]