isbn-verifier: Normalize whitespace in metadata file
isbn-verifier: Normalize whitespace in metadata file

This whitespace change is what I get when I open the file in my editor and save it.
I assume that the difference is a newline at the end of the file, which I believe is normal for
files edited in text editors.

ErikSchierboom/x-common,ErikSchierboom/x-common,rpottsoh/x-common,petertseng/x-common,jmluy/x-common,petertseng/x-common,jmluy/x-common,exercism/x-common,jmluy/x-common,rpottsoh/x-common,exercism/x-common