Fix check-replication compatibility in 9.x

Author: phumpal

CHANGELOG.md

@@ -4,6 +4,8 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 This CHANGELOG follows the format listed [here](https://github.com/sensu-plugins/community/blob/master/HOW_WE_CHANGELOG.md).
 
 ## [Unreleased]
+### Fixed
+- check-postgres-replication.rb: fix 9.x compatibility
 
 ## [1.4.3] - 2017-11-06
 ### Fixed

bin/check-postgres-replication.rb

@@ -106,7 +106,7 @@ def compute_lag(master, slave, m_segbytes)
 
   def check_vsn(conn)
     pg_vsn = conn.exec("SELECT current_setting('server_version')").getvalue(0, 0)
-    return if Gem::Version.new(pg_vsn) < Gem::Version.new('10.0') && Gem::Version.new(pg_vsn) >= Gem::Version.new('9.0')
+    Gem::Version.new(pg_vsn) < Gem::Version.new('10.0') && Gem::Version.new(pg_vsn) >= Gem::Version.new('9.0')
   end
 
   def run