String indices must be indices error when calling list_active_stores()

[stfines-clgx]

Describe the bug
In attempting to create a dynamically provisioned context for a data validation pipeline, I ran across this error:

Traceback (most recent call last):
  File "/Users/stfines/Library/Caches/pypoetry/virtualenvs/airflow-great-expectations-dag-yAcbwmv7-py3.11/lib/python3.11/site-packages/IPython/core/interactiveshell.py", line 3550, in run_code
    exec(code_obj, self.user_global_ns, self.user_ns)
  File "<ipython-input-23-77496d5f7fe7>", line 1, in <module>
    ctx.list_active_stores()
  File "/Users/stfines/Library/Caches/pypoetry/virtualenvs/airflow-great-expectations-dag-yAcbwmv7-py3.11/lib/python3.11/site-packages/great_expectations/data_context/data_context/abstract_data_context.py", line 1221, in list_active_stores
    self.expectations_store_name,  # type: ignore[list-item]
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/stfines/Library/Caches/pypoetry/virtualenvs/airflow-great-expectations-dag-yAcbwmv7-py3.11/lib/python3.11/site-packages/great_expectations/data_context/data_context/abstract_data_context.py", line 549, in expectations_store_name
    return self.variables.expectations_store_name
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/stfines/Library/Caches/pypoetry/virtualenvs/airflow-great-expectations-dag-yAcbwmv7-py3.11/lib/python3.11/site-packages/great_expectations/data_context/data_context_variables.py", line 171, in expectations_store_name
    return self._get(DataContextVariableSchema.EXPECTATIONS_STORE_NAME)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/stfines/Library/Caches/pypoetry/virtualenvs/airflow-great-expectations-dag-yAcbwmv7-py3.11/lib/python3.11/site-packages/great_expectations/data_context/data_context_variables.py", line 123, in _get
    val: Any = self.config[key]
               ~~~~~~~~~~~^^^^^
TypeError: string indices must be integers, not 'str'

To Reproduce
Please include your great_expectations.yml config, the code you’re executing that causes the issue, and the full stack trace of any error(s).

Create an empty file context following the tutorial.

use something like this like this to set the active config:

def construct_expectation_store(context, project_name, bucket_name):
    context.set_config("""
    "expectations_store_name": 
            "class_name": "ExpectationsStore"
            "store_backend": 
                "class_name": "TupleGCSStoreBackend"
                "project": "{project_name}"
                "bucket": "{bucket_name}"
                "prefix": "/expectations"
        "validations_store_name": 
            "class_name": "ValidationsStore"
            "store_backend": 
                "class_name": "TupleGCSStoreBackend"
                "project": "{project_name}"
                "bucket": "{bucket_name}"
                "prefix": "/validations"
        "profiler_store_name": 
            "class_name": "ProfilerStore"
            "store_backend": 
                "class_name": "TupleGCSStoreBackend"
                "project": "{project_name}"
                "bucket": "{bucket_name}"
                "prefix": "/profiles"
        "evaluation_parameter_store_name": 
            "class_name": "EvaluationParameterStore"
            "store_backend":
                "class_name": "TupleGCSStoreBackend"
                "project": "{project_name}" 
                "bucket": "{bucket_name}"
                "prefix": "/evaluation_parameters"  
        "checkpoint_store_name":
            "class_name": "CheckpointStore"
            "store_backend":
                "class_name": "TupleGCSStoreBackend"
                "project": "{project_name}"
                "bucket": "{bucket_name}"
                "prefix": "/checkpoints"
        """.format(
            project_name=project_name, bucket_name=bucket_name
        )

then call ctx.list_active_stores()

Expected behavior
I would expect that the store name would be set from the configuration after calling set_config()

Environment (please complete the following information):

• Operating System: [e.g. Linux, MacOS, Windows]
  MacOs
• Great Expectations Version: [e.g. 0.13.2]
  18.13
• Data Source: [e.g. Pandas, Snowflake]
  N/A
• Cloud environment: [e.g. Airflow, AWS, Azure, Databricks, GCP]
  N/A

Additional context
This was replicated using the python 3.11 repl.

[molliemarie]

Hello @stfines-clgx. With the launch of Great Expectations Core (GX 1.0), we are closing old issues posted regarding previous versions. Moving forward, we will focus our resources on supporting and improving GX Core (version 1.0 and beyond). If you find that an issue you previously reported still exists in GX Core, we encourage you to resubmit it against the new version. With more resources dedicated to community support, we aim to tackle new issues swiftly. For specific details on what is GX-supported vs community-supported, you can reference our integration and support policy.

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Thank you for being part of the GX community and thank you for submitting this issue. We're excited about this new chapter and look forward to your feedback on GX Core. 🤗