fix(valkey): pin to major release (8)

After a discussion with @lbarcziova and revisiting the reappearing MP+
vulnerability reports, I've noticed I pinned the Valkey to use 8.0.0.

We do not strictly require the 8.0.0 and one patch release has already
happened, so I'm relaxing this requirement to require only major release
8.

Signed-off-by: Matej Focko <[email protected]>

Author: mfocko

openshift/valkey.yml.j2

@@ -26,7 +26,7 @@ spec:
     spec:
       containers:
         - name: valkey
-          image: valkey/valkey:8.0.0
+          image: valkey/valkey:8
           args:
             - "/etc/redislike/redis.conf"
           ports: