Increase CI job timeout to 2 hours

If there is a change to kolla then images are built, which can push the
job over the existing 1.5 hour timeout. These jobs are also used in the
kolla CI.

Change-Id: I88a28745cf834376163ced36984c317fce831346

zuul.d/base.yaml

@@ -5,7 +5,7 @@
     run: tests/run.yml
     post-run: tests/post.yml
     attempts: 1
-    timeout: 5400
+    timeout: 7200
     required-projects:
       - openstack/kolla
       - openstack/requirements