Survival analysis DataLoader silently removes data rows

[ZhaozhiQIAN]

The code below will silently remove rows from the original data set:

synthcity/src/synthcity/plugins/core/dataloader.py

Line 511 in 2f6fdb3

data = data[T > 0]

In some encoding schemes, T = -1 indicates censored patients. These patients would be removed using the T > 0 filleter.

I will add an exception when this happens.