relay non-zero exit codes when creating openvswitch bridges

Calls to `ovs-vsctl` in `ovs_ensure_configured.sh` did not get checked
for errors.
This can cause false success statuses when
the script is run by automation tools such as ansible.

Depends-On: https://review.opendev.org/c/openstack/kolla-ansible/+/870540

Closes-bug: #1999778
Change-Id: Iad83132b61efadbf09aa9aa2edf96235085764c6

docker/openvswitch/openvswitch-db-server/ovs_ensure_configured.sh

@@ -1,16 +1,15 @@
 #!/bin/bash
+set -o errexit
 
 bridge=$1
 port=$2
 
-ip link show $port
-if [[ $? -ne 0 ]]; then
+if ! ip link show $port; then
     # fail when device doesn't exist
     exit 1
 fi
 
-ovs-vsctl br-exists $bridge
-if [[ $? -eq 2 ]]; then
+ovs-vsctl br-exists $bridge || if [[ $? -eq 2 ]]; then
     changed=changed
     ovs-vsctl --no-wait add-br $bridge
 fi

releasenotes/notes/bug-1999778.yaml

@@ -0,0 +1,7 @@
+---
+fixes:
+  - |
+    Fixes an issue where the script ``kolla_ensure_openvswitch_configured`` in
+    the ``openvswitch-db-server`` image would ignore errors encountered while
+    configuring bridges and ports.
+    `LP#1999778 <https://launchpad.net/bugs/1999778>`__