I'm seeing quite a few of these in prod:

```
java.lang.NullPointerException: Cannot invoke "org.elasticsearch.xpack.core.transform.transforms.TransformState.getTaskState()" because "transformState" is null
    at org.elasticsearch.xpack.transform.TransformUsageTransportAction.masterOperation(TransformUsageTransportAction.java:106) ~[?:?]
    at org.elasticsearch.xpack.transform.TransformUsageTransportAction.masterOperation(TransformUsageTransportAction.java:55) ~[?:?]
    at org.elasticsearch.action.support.master.TransportMasterNodeAction.executeMasterOperation(TransportMasterNodeAction.java:124) ~[elasticsearch-8.9.0.jar:?]
    at org.elasticsearch.action.support.master.TransportMasterNodeAction$AsyncSingleAction.lambda$doStart$3(TransportMasterNodeAction.java:235) ~[elasticsearch-8.9.0.jar:?]
    at org.elasticsearch.action.ActionRunnable$3.doRun(ActionRunnable.java:72) ~[elasticsearch-8.9.0.jar:?]
    at org.elasticsearch.common.util.concurrent.ThreadContext$ContextPreservingAbstractRunnable.doRun(ThreadContext.java:983) ~[elasticsearch-8.9.0.jar:?]
    at org.elasticsearch.common.util.concurrent.AbstractRunnable.run(AbstractRunnable.java:26) ~[elasticsearch-8.9.0.jar:?]
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1144) ~[?:?]
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:642) ~[?:?]
    at java.lang.Thread.run(Thread.java:1623) ~[?:?]
```

`org.elasticsearch.persistent.PersistentTasksCustomMetadata.PersistentTask#getState` is declared `@Nullable` but this case is not handled properly by the usage action.
x-pack/plugin/transform/src/main/java/org/elasticsearch/xpack/transform/action/TransportStartTransformAction.java
new ValidateTransformAction.Request(config, false, request.timeout()),
                validationListener
            );
        }, listener::onFailure);
        
        ActionListener<TransformConfig> getTransformListener = ActionListener.wrap(config -> {
            transformConfigHolder.set(config);
            if (Boolean.TRUE.equals(config.getSettings().getUnattended())) {
                
                
                fetchAuthStateListener.onResponse(null);
            } else {
                AuthorizationStatePersistenceUtils.fetchAuthState(transformConfigManager, request.getId(), fetchAuthStateListener);
            }
        }, listener::onFailure);
        
        transformConfigManager.getTransformConfiguration(request.getId(), getTransformListener);
    }
    @Override
    protected ClusterBlockException checkBlock(StartTransformAction.Request request, ClusterState state) {
        return state.blocks().globalBlockedException(ClusterBlockLevel.METADATA_WRITE);
    }
    private void cancelTransformTask(String taskId, String transformId, Exception exception, Consumer<Exception> onFailure) {
        persistentTasksService.sendRemoveRequest(taskId, new ActionListener<>() {
            @Override
            public void onResponse(PersistentTasksCustomMetadata.PersistentTask<?> task) {
                
                
                onFailure.accept(exception);
            }