Update monitoring plugin

Change-Id: Id3d4a9418a9ae43899ef9c17768c26a54ffb5528
diff --git a/jenkins-docker/master/plugins.txt b/jenkins-docker/master/plugins.txt
index 42fa70f..a0d037c 100644
--- a/jenkins-docker/master/plugins.txt
+++ b/jenkins-docker/master/plugins.txt
@@ -61,7 +61,7 @@
 matrix-project:1.13
 mercurial:2.6
 momentjs:1.1.1
-monitoring:1.73.0
+monitoring:1.81.0
 pipeline-build-step:2.7
 pipeline-graph-analysis:1.9
 pipeline-input-step:2.8