feat: add a chart util for display ChartExecutorResponse

[bx-h]

#52

[bx-h]

@microsoft-github-policy-service agree

[victordibia]

Hi @bx-h ,

Thanks for this, it makes a bit of progress in addressing #52.
I was thinking of a much simpler solution ie. extending ChartExecutor response directly.
I pushed that change. Main approach

• Add a savefig to ChartExecutor directly in datamodel.py. This avoids adding an new file to the codebase.
• Does not add any additional dependencies e.g. cv2, . This makes the library ligther.

Finally, I think displaying the image should be implemented outside the library, as many applications may chose to visualization an image in different ways.

In terms of your PR, while change e428 covers a bit of it, I think extending the tests you added would be valuable here

[bx-h]

Hi @victordibia ,
You're right! I've updated the test cases following your suggestion.