feature: integrate amtviz for visualization of tuning jobs

[uyoldas]

Description of changes: Add new functionality to HyperparameterTuner class to visualize the results of tuning jobs. The class now contains two functions using the amtviz package to create dynamic and interactive charts visualizing the influence of hyperparameters on the objective metric. The code in amtviz uses altair for charts generation. The original repository can be found here:
https://github.com/aws-samples/amazon-sagemaker-amt-visualize/

Testing done: Yes, added new unit tests and ran them successfully.

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