Tempest test for Neutron extension: extraroute-atomic

Change-Id: I9b104432f1cd1aa1471087226ffc53152b823222
Depends-On: https://review.opendev.org/670851
Partial-Bug: #1826396 (rfe)
Related-Change: https://review.opendev.org/655680 (spec)
diff --git a/.zuul.yaml b/.zuul.yaml
index 011bfe5..00be4ed 100644
--- a/.zuul.yaml
+++ b/.zuul.yaml
@@ -31,6 +31,7 @@
         - external-net
         - extra_dhcp_opt
         - extraroute
+        - extraroute-atomic
         - filter-validation
         - fip-port-details
         - flavors