Empty line (of comma's) in a NextSeq sample sheet causes error

[JeffreyThiessen]

Describe the bug

If the last line of the sample sheet is a bunch of commas like an empty row generated in excel
,,,,,,,,,
The following error reads
The uploader was unable to find the directory '' in 'Path/to/file/dir', Please verify your SampleSheet Sample_Project matches the directory structure.

This happens because it's looking for a folder with no characters/empty string.

Expected behaviour

It should skip lines that are empty like this.