Update paho.mqtt.golang (#6149)

Gopkg.lock

@@ -384,15 +384,15 @@
   version = "v1.1.0"
 
 [[projects]]
-  digest = "1:3fa846cb3feb4e65371fe3c347c299de9b5bc3e71e256c0d940cd19b767a6ba0"
+  digest = "1:392ebbe504a822b15b41dd09cecc5baa98e9e0942502950dc14ba1f23c149e32"
   name = "github.com/eclipse/paho.mqtt.golang"
   packages = [
     ".",
     "packets",
   ]
   pruneopts = ""
-  revision = "36d01c2b4cbeb3d2a12063e4880ce30800af9560"
-  version = "v1.1.1"
+  revision = "adca289fdcf8c883800aafa545bc263452290bae"
+  version = "v1.2.0"
 
 [[projects]]
   digest = "1:99a0607f79d36202b64b674c0464781549917cfc4bfb88037aaa98b31e124a18"

Gopkg.toml

@@ -40,7 +40,7 @@
 
 [[constraint]]
   name = "github.com/eclipse/paho.mqtt.golang"
-  version = "~1.1.1"
+  version = "1"
 
 [[constraint]]
   name = "github.com/go-sql-driver/mysql"

plugins/inputs/mqtt_consumer/mqtt_consumer_test.go

@@ -90,6 +90,10 @@ func (m *message) Duplicate() bool {
 	return m.duplicate
 }
 
+func (m *message) Ack() {
+	return
+}
+
 func (m *message) Qos() byte {
 	return m.qos
 }