Allow get_column_plot to graph synthetic and real data individually

[lajohn4747]

Part 2 of 3 for allowing visualizations to work with a single dataset: #581
CU-86b0t56r9

This PR is to handle get_column_plot

[sdv-team]

Task linked: CU-86b0t56r9 SDMetrics - Allow me to visualize just the real or synthetic data #581

[npatki]

Hi @lajohn4747 the request was to always have the correct color -- so when you're doing synthetic data, it should be light blue, not dark blue. However, all of your graphs are the darker color. Could you update this?

[amontanez24]

Looks good but it doesn't seem like there are any unit tests for _generate_column_plot and that is mocked in the test for get_column_plot so a lot of this functionality seems to be untested. This seems to come from before this PR but can you either

1. Add tests for _generate_column_plot or
2. Remove the mock and make sure everything is behaving as expected
   If you do the second one you can mock px and ff so you don't have to graph anything and can just ealuate the right inputs are being passed

[amontanez24]