redis HA: allow SELinux relabel for /var/run/redis

/var/run/redis is bind-mounted from the host, and on every reboot
that directory is recreated with default context for the host.

Configure the bind-mount so that /var/run/redis is relabelled
with a container context every time the redis container is started,
so that kolla can copy its config file and update the owner and
attributes as expected without SELinux denials.

Change-Id: Iaa8a99eb9ced21fb6c7c87c5b56dec55383af9a9
Partial-Bug: #1826554

manifests/profile/pacemaker/database/redis_bundle.pp

@@ -266,7 +266,7 @@ slave-announce-port ${local_tuple[0][2]}
         'redis-run'                     => {
           'source-dir' => '/var/run/redis',
           'target-dir' => '/var/run/redis',
-          'options'    => 'rw',
+          'options'    => 'rw,z',
         },
         # TODO check whether those tls mappings are necessary
         'redis-pki-extracted'           => {