Exclude watcher-operator-index- image in env_op_images role

watcher-operator is going to shipped as a standalone operator.
It is going to be installed via olm seperatly from index image in openstack-operators
namespace.

when env_ops_images creates operator_images dictionary, it goes over all
the pods listed under openstack-operators namespace with label openstack.org/operator-name
which does not exists for watcher-operator-index- pod. It fails with
following error[1]:
```
The task includes an option with an undefined variable.
The error was: 'dict object' has no attribute 'openstack.org/operator-name'. 'dict object' has no attribute 'openstack.org/operator-name'
```

This pr excluded the watcher-operator-index- pod to fix the issue.

Links:
[1]. openstack-k8s-operators/watcher-operator#9 (comment)

Signed-off-by: Chandan Kumar <[email protected]>

roles/env_op_images/tasks/main.yml

@@ -119,7 +119,8 @@
           RABBITMQ_OP_IMG: "{{ selected_pod.status.containerStatuses[0].imageID }}"
         selected_pods: "{{ pod_list.resources |
                            rejectattr('metadata.generateName', 'contains', 'openstack-operator-index-') |
-                           rejectattr('metadata.generateName', 'contains', 'rabbitmq-cluster-operator-')
+                           rejectattr('metadata.generateName', 'contains', 'rabbitmq-cluster-operator-') |
+                           rejectattr('metadata.generateName', 'contains', 'watcher-operator-index-')
                         }}"
 
     - name: Add operator images to the dictionary