[BUG] If no actual_label is provided, color by correctness results in an empty view

[mikeldking]

Describe the bug
As seen during usability study w/ @hakantekgul , if you don't provide actuals or predictions, the TP, TN, FN, FP confusion matrix values cannot be computed, leaving the point-cloud empty.

To Reproduce
Steps to reproduce the behavior:

1. Upload a single dataset with no predictions
2. click on the embedding
   Nothing is visible

Expected behavior
At least draw the points.

Environment (please complete the following information):
N/A