great_expectations: batch_request passed in to SimpleCheckpoint errors

Describe the bug When creating a SimpleCheckpoint and passing in a batch_request: BatchRequest, it seems to treat the batch_request as a dictionary instead of a BatchRequest and errors out AttributeError: 'BatchRequest' object has no attribute 'items' here

To Reproduce Steps to reproduce the behavior:

import great_expectations as ge
from great_expectations.core.batch import RuntimeBatchRequest
from great_expectations.cli.datasource import sanitize_yaml_and_save_datasource
from great_expectations.checkpoint import SimpleCheckpoint

import pandas as pd


context = ge.get_context()
df = pd.DataFrame({"col1": ["a", "a", "b", "c"], "col2": [1, 2, 3, 4]})
config = """
    name: my_pandas_datasource
    class_name: Datasource
    execution_engine:
        class_name: PandasExecutionEngine
    data_connectors:
        my_runtime_data_connector:
          class_name: RuntimeDataConnector
          batch_identifiers:
              - some_batch_identifier_so_this_can_work
"""



context.test_yaml_config(
    yaml_config=config
)
sanitize_yaml_and_save_datasource(context, config, overwrite_existing=True)


runtime_batch_request = RuntimeBatchRequest(
    datasource_name="my_pandas_datasource",
    data_connector_name="my_runtime_data_connector",
    data_asset_name="insert_your_data_asset_name_here",
    runtime_parameters={
      "batch_data": df
    },
    batch_identifiers={
        "some_batch_identifier_so_this_can_work": "blah",
    }
)
my_checkpoint = SimpleCheckpoint(
    name="my_checkpoint",
    data_context=context,
    batch_request = runtime_batch_request
)

>>

AttributeError                            Traceback (most recent call last)
<ipython-input-1-b72466658554> in <module>
     43     name="my_checkpoint",
     44     data_context=context,
---> 45     batch_request = runtime_batch_request
     46 )

~/.pyenv/versions/anaconda3-2020.02/envs/sandbox/lib/python3.7/site-packages/great_expectations/checkpoint/checkpoint.py in __init__(self, name, data_context, config_version, template_name, module_name, class_name, run_name_template, expectation_suite_name, batch_request, action_list, evaluation_parameters, runtime_configuration, validations, profilers, validation_operator_name, batches, site_names, slack_webhook, notify_on, notify_with, **kwargs)
    672             slack_webhook=slack_webhook,
    673             notify_on=notify_on,
--> 674             notify_with=notify_with,
    675         ).build()
    676 

~/.pyenv/versions/anaconda3-2020.02/envs/sandbox/lib/python3.7/site-packages/great_expectations/checkpoint/configurator.py in build(self)
    112         self._validate_slack_configuration()
    113 
--> 114         return self._build_checkpoint_config()
    115 
    116     def _build_checkpoint_config(self) -> CheckpointConfig:

~/.pyenv/versions/anaconda3-2020.02/envs/sandbox/lib/python3.7/site-packages/great_expectations/checkpoint/configurator.py in _build_checkpoint_config(self)
    134                         "config_version": self.other_kwargs.pop("config_version", 1.0)
    135                         or 1.0,
--> 136                         **self.other_kwargs,
    137                     }
    138                 )

~/.pyenv/versions/anaconda3-2020.02/envs/sandbox/lib/python3.7/site-packages/great_expectations/data_context/types/base.py in update(self, other_config, runtime_kwargs)
   1743                 updated_batch_request = nested_update(
   1744                     batch_request,
-> 1745                     other_batch_request,
   1746                 )
   1747                 self._batch_request = updated_batch_request

~/.pyenv/versions/anaconda3-2020.02/envs/sandbox/lib/python3.7/site-packages/great_expectations/core/util.py in nested_update(d, u, dedup)
     69 ):
     70     """update d with items from u, recursively and joining elements"""
---> 71     for k, v in u.items():
     72         if isinstance(v, Mapping):
     73             d[k] = nested_update(d.get(k, {}), v, dedup=dedup)

AttributeError: 'RuntimeBatchRequest' object has no attribute 'items'

Expected behavior I expected the above to work since I’m passing in batch_request: BatchRequest

Environment (please complete the following information):

• Operating System: MacOS
• Great Expectations Version: 0.13.17

Additional context None