Update opensciencegrid/gracc-apel/docker-run.sh

Co-authored-by: jthiltges <jthiltges2@unl.edu>

Author: djw8605

opensciencegrid/gracc-apel/docker-run.sh

@@ -7,7 +7,7 @@ echo "$wrote"
 apelfile=${wrote#wrote: }
 
 # Output the content of the apelfile before uploading, for debugging purposes
-cat $apelfile
+cat "$apelfile"
 
 cp "$apelfile" /var/spool/apel/outgoing/12345678/1234567890abcd