Description of changes:
Added an optional parameter 'num_clusters' to SHAPConfig class to allow users to specify the number of clusters used by K-Means clustering. This parameter is used when a baseline dataset is not provided for SHAP, so a dataset is generated using K-means clustering. Code ensures baseline and num_clusters parameters aren't both passed, since they are mutually exclusive.

Testing done:
Unit Testing

1. test_clarify::test_shap_config_no_baseline -> Validates that SHAPConfig object without baseline and with num_clusters can be created
2. test_clarify::test_shap_config_no_parameters -> Validates that SHAPConfig object without any provided parameters can be created
3. test_clarify::test_invalid_shap_config -> Validates that providing baseline and num_clusters parameters to SHAPConfig results in an error

End to End Testing
For documentation purposes, Clarify integration tests using below objects ran successfully.

1. SHAPConfig(num_samples=2, agg_method="mean_sq", seed=123)
2. SHAPConfig(num_samples=2, agg_method="mean_sq", seed=123, num_clusters=3)

Merge Checklist

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Tests

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