fix(valkey): pin to major release (8) (#612)

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.
State of deployment:

 stage
 prod

Reviewed-by: Laura Barcziová

Author: softwarefactory-project-zuul[bot]

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: