Reproduce issue with file paths ending `/` for `Convert Cellvoyager Multiplexing to OME-Zarr`

Reported by Kelvin:

> I also noticed that when adding the Image Dir in convert cellvoyager multiplexing to ome-zarr that the image dir has to end with a /. I get an error message with no plate found. I think it simply is not able to find the files in the directory

Let's try to reproduce the way the task is sensitive to the paths ending with a `/` and then fix that