Honour the linuxbridge experimental status

This patch follows upstream and disables linuxbridge testing.

Kolla part.

Change-Id: I9f77e782df9e4ddcdd4be536b4cce668b728824e

.zuul.d/ubuntu.yaml

@@ -59,10 +59,6 @@
             files: ^docker/(base|masakari|openstack-base)/
             vars:
               kolla_python_version: "3.10"
-        - kolla-ansible-ubuntu-source-linuxbridge:
-            files: ^docker/(base|neutron|openstack-base)/
-            vars:
-              kolla_python_version: "3.10"
         - kolla-ansible-ubuntu-source-octavia:
             files: ^docker/(base|neutron|octavia|openstack-base|openvswitch|ovn)/
             vars:

README.rst

@@ -130,7 +130,7 @@ Kolla provides images to deploy the following infrastructure components:
 - `MariaDB and Galera Cluster <https://mariadb.com/kb/en/library/galera-cluster/>`__
   for highly available MySQL databases.
 - `Memcached <https://www.memcached.org/>`__ a distributed memory object caching system.
-- `Open vSwitch <https://www.openvswitch.org/>`__ and Linuxbridge back ends for Neutron.
+- `Open vSwitch <https://openvswitch.org/>`__ for use with Neutron.
 - MariaDB Backup A tool which provides a method of performing a hot backup of your MySQL data while the
   system is running.
 - `Prometheus <https://prometheus.io/>`__ an open-source systems monitoring