Fix a missing import.

Change-Id: I2961ff959c1bb63de9232c6f6c40097e2e53b23d
diff --git a/cicd/pipelines/tasks/task_publish_unstable.jenkins b/cicd/pipelines/tasks/task_publish_unstable.jenkins
index baae01d..bf28e93 100644
--- a/cicd/pipelines/tasks/task_publish_unstable.jenkins
+++ b/cicd/pipelines/tasks/task_publish_unstable.jenkins
@@ -1,5 +1,7 @@
 #!/usr/bin/env groovy
 
+library 'functions'
+
 def updateBspPublish(String boardName) {
     def bspSnapshotName  = functions.getLatestSnapshot("unstable-bsp-${boardName}")