Merge pull request #4477 from edx/jibsheet/fix-service_variant-comment

Fix the comment to match the regexp

playbooks/roles/common/templates/edx_rsyslog.j2

@@ -26,7 +26,7 @@ auth,authpriv.*                                         /var/log/auth.log
 # Maybe one day this will be answered - http://stackoverflow.com/questions/10449447/how-to-avoid-syslogtag-from-rsyslog-template
 $template tracking,"%syslogtag%%msg%\n"
 
-# looks for [service_name=<name>] in the beginning of the log message,
+# looks for [service_variant=<name>] in the beginning of the log message,
 # if it exists the log will go into {{ COMMON_LOG_DIR }}/<name>/edx.log, otherwise
 # it will go into {{ COMMON_LOG_DIR }}/edx.log
 $template DynaFile,"{{ COMMON_LOG_DIR }}/%syslogtag:R,ERE,1,BLANK:\[service_variant=([a-zA-Z_-]*)\].*--end%/edx.log"