Which are the states including the common SFN states for which <state>.output () can be applied ?

This is a separate issue created from the discussion by @nsankar addressed to @wong-a from the issue id #31
The key point is which are the common SFN and AWS specific service states where we can use the form `.output()` in this SDK. Please include it in the documentation.

More details and an example state using output() is as under.,

(1) Which are the states including the common SFN states for which state output () is applicable **or** can be used? This is not in the document unless we see an example, for instance, as an example output () is applicable to the processing step which can be then used in a choice state as cited below:

```
processing_step = ProcessingStep(
"SageMaker processing step",
processor=script_processor,
job_name=execution_input["PreprocessingJobName"], ## placeholder per schema above. Later in workflow execute() below pass the uuid of jobname
inputs=inputs,
outputs=outputs,
# container_arguments=["--train-test-split-ratio", "0.2"],
container_entrypoint=["python3", "/opt/ml/processing/input/code/myprogram.py"],
)

choice_state1.add_choice(ChoiceRule.StringEquals(processing_step**.output()**["ProcessingJobStatus"], "Completed"), lambda_state1)

```

该 issue 提到了 ProcessingStep、ChoiceRule.StringEquals 和状态输出 output()，但没有指出文档文件或测试。首先定位有关工作流状态的 SDK 文档和 ProcessingStep 示例，然后确定哪些通用状态和 AWS 特定状态支持 output()。当文档列出适用的状态并包含一个可运行的示例时，即视为完成。

由索引模型根据 Issue 内容生成。