Extend the timeout for DIB tests

When performing image boot tests we run up against the 30min default
timeout. We are pretty far in the test run at this point, so extenting
the timeout to 60min should be enough.

Change-Id: I0254e08e2bee35f4db5ec9deb185e328e67a6d5a

jenkins/jobs/diskimage-builder.yaml

@@ -2,6 +2,11 @@
     name: 'gate-dib-dsvm-functests-{node}'
     node: '{node}'
 
+    wrappers:
+      - build-timeout:
+          timeout: 60
+      - timestamps
+
     builders:
       - shell: |
           #!/bin/bash -eux