Fixed #1372 -- sleep before checking if the build completed to ensure the buidl exists

tasks.py

diff --git a/tasks.py b/tasks.py
index 2dd005b..c109f14 100644
--- a/tasks.py
+++ b/tasks.py
@@ -17,6 +17,9 @@
 
 
 def wait_for_build_completed(session):
+    # Wait 3 seconds before actually checking if the build is complete, to
+    # ensure that it had time to really start.
+    time.sleep(3)
     while True:
         response = session.get(
             "{0}/lastBuild/api/json/".format(JENKINS_URL),