prodvider: clean up LDAP connections

Change-Id: Ic95e6d1b845832fa0fb2da51b418bcdcb8fd05c4
diff --git a/cluster/prodvider/service.go b/cluster/prodvider/service.go
index 5635ac2..0409884 100644
--- a/cluster/prodvider/service.go
+++ b/cluster/prodvider/service.go
@@ -38,6 +38,7 @@
 		glog.Errorf("ldap.DialTLS: %v", err)
 		return nil, status.Error(codes.Unavailable, "could not context LDAP")
 	}
+	defer lconn.Close()
 
 	dn := fmt.Sprintf(flagLDAPBindDN, username)
 	err = lconn.Bind(dn, password)