### 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
* Important: Might call into TransformTask, this should _only_ be called with an acquired indexer lock if and only if
     * the lock for TransformTask has been acquired, too. See gh#75846
     *
     * (Note: originally this method was synchronized, which is not necessary)
     */
    void handleFailure(Exception e) {
        logger.warn(() -> "[" + getJobId() + "] transform encountered an exception: ", e);
        Throwable unwrappedException = ExceptionsHelper.findSearchExceptionRootCause(e);
        if (unwrappedException instanceof CircuitBreakingException) {
            handleCircuitBreakingException((CircuitBreakingException) unwrappedException);
            return;
        }
        if (unwrappedException instanceof ScriptException) {
            handleScriptException((ScriptException) unwrappedException);
            return;
        }
        if (unwrappedException instanceof BulkIndexingException && ((BulkIndexingException) unwrappedException).isIrrecoverable()) {
            handleIrrecoverableBulkIndexingException((BulkIndexingException) unwrappedException);
            return;
        }
        
        if (unwrappedException instanceof ElasticsearchException elasticsearchException) {
            if (ExceptionRootCauseFinder.IRRECOVERABLE_REST_STATUSES.contains(elasticsearchException.status())) {
                failIndexer("task encountered irrecoverable failure: " + elasticsearchException.getDetailedMessage());
                return;
            }
        }
        if (unwrappedException instanceof IllegalArgumentException) {
            failIndexer("task encountered irrecoverable failure: " + e.getMessage());
            return;