Fix reading empty lines

I'm pretty sure shadow(5) guarantees this won't happen but best to be safe

wayblue-fix-89.sh

@@ -43,6 +43,9 @@ for file in /etc/shadow /etc/gshadow; do
 	echo "Parsing $file for junk"
 	# Read each line in the file to iterate over it
 	while read line; do
+		# This should never happen, but if for some reason we get an empty line,
+		# continue
+		[ -z "$line" ] && continue
 		# Per shadow(5), we are guaranteed that all characters leading up to the
 		# first colon are the user's/group's name. To that end, we'll do a bash
 		# string substitution to extract that first column.