TT#160551 Remove percona replication check support

This check breaks Carrier replication so it was removed. Remove the
corresponding test.

Change-Id: I4220a68a85fa58967e7cd9275dc9425017c2448d

templates/915_service-snmp.yaml.tt2

@@ -49,7 +49,6 @@ command:
     - "/::dbSlaveSQLLastErrorDesc\\.\\d\\.\\d = /"
     - "/::dbQueryRate\\.\\d\\.\\d = /"
     - "/::dbReplDelay\\.\\d\\.\\d = /"
-    - "/::dbReplDiff\\.\\d\\.\\d = /"
     - "/::load\\dmin\\.\\d = /"
     - "/::load5min\\.\\d = /"
     - "/::load\\d5min\\.\\d = /"