Mount my.cnf.d into the db_sync container for Barbican and Octavia.

This ensures that the generated my.cnf.d configurations are present
in the Barbican and Octavia db_sync containers. Without these settings,
a MySQL authentication error stops the db sync when TLS is enabled for
MySQL.

Change-Id: I8aaabf013b50b963e9a973b2ccedcbd4f6a9197d
Closes-Bug: 1782392

docker/services/barbican-api.yaml

@@ -138,6 +138,7 @@ outputs:
                 - {get_attr: [BarbicanApiLogging, volumes]}
                 -
                   - /var/lib/config-data/barbican/etc/barbican/:/etc/barbican/:ro
+                  - /var/lib/config-data/barbican/etc/my.cnf.d/:/etc/my.cnf.d/:ro
             command:
               # NOTE(jaosorior): When providing extra arguments, we need to make sure that they're part
               # of the bash -c invocation, so we include them in the quoted db sync command. Hence the

docker/services/octavia-api.yaml

@@ -139,6 +139,7 @@ outputs:
                 - {get_attr: [ContainersCommon, volumes]}
                 -
                   - /var/lib/config-data/octavia/etc/octavia/:/etc/octavia/:ro
+                  - /var/lib/config-data/octavia/etc/my.cnf.d/:/etc/my.cnf.d/:ro
                   - /var/log/containers/octavia:/var/log/octavia
                   - /var/log/containers/httpd/octavia-api:/var/log/httpd
             command: "/usr/bin/bootstrap_host_exec octavia_api su octavia -s /bin/bash -c '/usr/bin/octavia-db-manage upgrade head'"