### Description

Currently, when we execute retention policy, we also refresh the destination index by setting:
```
setRefresh(true)
```
on the DBQ request.
This can cause permission errors which are surprising to the user as the permissions are not required when the transform starts:
```
task encountered irrecoverable failure: org.elasticsearch.ElasticsearchSecurityException: action [indices:admin/refresh] is unauthorized for user [found-internal-kibana4-server] with roles [kibana_system,found-internal-kibana4-server] on indices [logs-cloud_security_posture.findings_latest-default], this action is granted by the index privileges [maintenance,manage,all]
```

We still want the user to have the permissions to delete the documents. But we should execute `refresh` as the system user.
x-pack/plugin/transform/src/main/java/org/elasticsearch/xpack/transform/transforms/TransformIndexer.java
} catch (InterruptedException e) {
            logger.error(
                () -> format(
                    "[%s] Interrupt waiting (%ss) for transform state to be stored.",
                    getJobId(),
                    PERSIST_STOP_AT_CHECKPOINT_TIMEOUT_SEC
                ),
                e
            );
            
            shouldStopAtCheckpointListener.onFailure(
                new RuntimeException(
                    "Timed out (" + PERSIST_STOP_AT_CHECKPOINT_TIMEOUT_SEC + "s) waiting for transform state to be stored.",
                    e
                )
            );
        } catch (Exception e) {
            logger.error(() -> "[" + getJobId() + "] failed to persist transform state.", e);
            shouldStopAtCheckpointListener.onFailure(e);
        }
    }
    private boolean addSetStopAtCheckpointListener(boolean shouldStopAtCheckpoint, ActionListener<Void> shouldStopAtCheckpointListener)
        throws InterruptedException {
        synchronized (context) {
            
            if (indexerThreadShuttingDown) {
                context.setShouldStopAtCheckpoint(shouldStopAtCheckpoint);
                saveStateRequestedDuringIndexerThreadShutdown = true;
                return false;
            }