Feature/get test cases map

[jkshj21]

I added a function that returns the test cases map in https://github.com/GoogleCloudPlatform/dfcx-scrapi/blob/main/src/dfcx_scrapi/core/test_cases.py

the name of the function is "get_test_cases_map"

The description is like below:

    """Exports Agent Test Cases and UUIDs into a user friendly dict.

    Args:
      agent_id: The agent to create the test case for. Format:
          `projects/<Project ID>/locations/<Location ID>/agents/<Agent ID>`
      reverse: (Optional) Boolean flag to swap key:value -> value:key
    Returns:
      Dict containing Test Case UUIDs as keys and display names as values.
    """

[MRyderOC]

Made some typo changes on the last commit

[MRyderOC]

LGTM!

[MRyderOC]

@kmaphoenix Ready to merge!

[kmaphoenix]

LGTM