Omit id columns from metric calculations

[katxiao]

Problem Description

Columns of type id should be dropped when computing metrics. ID columns are not synthetically generated, so should not contribute to the metric calculation. Currently they are being classified as categorical, which is incorrect.

Expected behavior

DetectionMetric should use the provided metadata to drop id columns from the real and synthetic data when computing the metric. This logic should also be applied to any other relevant metrics.

[npatki]

Some metrics are are already implemented with the correct behavior. Eg any MultiSingleColumn metric (such as KSTest) has a declared set of field_types that it is compatible with. Only those fields are selected when computing the metric.

[npatki]

Seems like the detection metric hasn't used the metadata at all. We're using #119 to track this.

But we should keep this issue open as a general one for ID columns across any metric.