dash doesn't support bash-style filename expansion

Change-Id: I21c24d09673dd3f5ef9512a26b8b95852e309883
diff --git a/jobs.yaml b/jobs.yaml
index 6916e9e..82ac90a 100644
--- a/jobs.yaml
+++ b/jobs.yaml
@@ -38,7 +38,7 @@
       - timed: "@midnight"
     builders:
       - shell: stdbuf -oL -eL mispipe "~mininet/mininet/util/vm/build.py -v --test sanity {flavor}"  "tr '\r' ' '"
-      - shell: zip `basename -s .ovf */*.ovf`.zip */*.+(vmdk|ovf)
+      - shell: zip `basename -s .ovf */*.ovf`.zip */*.ovf */*.vmdk
     publishers:
       - archive:
             artifacts: '**'