Increase default build timeout to 120sec

Some tests are failing due to hitting the build timeout, for
now, lets increase this time in order to allow for tests to
pass while we look into the root cause of the slowdown.

Change-Id: I9efdb15a10dc22659dd3f682d58e6960692fc866
diff --git a/designate_tempest_plugin/config.py b/designate_tempest_plugin/config.py
index 1a4f2bd..5b99e81 100644
--- a/designate_tempest_plugin/config.py
+++ b/designate_tempest_plugin/config.py
@@ -38,7 +38,7 @@
                default=1,
                help="Time in seconds between build status checks."),
     cfg.IntOpt('build_timeout',
-               default=60,
+               default=120,
                help="Timeout in seconds to wait for an resource to build."),
     cfg.IntOpt('min_ttl',
                default=1,