[BUG] No error or warning while loading multiple datasets with mismatched columns

What issues are you experiencing?

When trying to use PyCytoData.FileIO.load_expression() to read a list of files with mismatched or different channel names, there is a bug that stems from the PyCytoData.FileIO.load_delim() method. There are a number of issues:

This error is currently undetected: namely, no error or warning is thrown.
The channels will be mismatched (in the order given by each file).
The channel names will be recorded as the channel names of the first file.

This occurs only when the number of channels is the same for each file, but further testing is needed.

To Reproduce

We need two files with the same number of channels in each. We can run the following to reproduce the issue:

files: list = ["<file_1>", "<file_2>"]

df = PyCytoData.FileIO.load_expression(files, delim = ",", col_names=True)
df.channels

Expected behavior

At least we should have a warning, but I think an error should be thrown because the current behavior is wrong. Although this technically can be a breaking change, I think we should fix this as a patch as otherwise we can unknowingly cause issues.

Your environment:

OS: WSL with Ubuntu
Python Version: 3.10.9
Python Distribution: Anaconda
PyCytoData version: 0.1.0
PyCytoData distribution: Anaconda

kevin931 / PyCytoData