Test: Fix reference to onepage-letter-*.pwg away from their old .gz postfix

This was changed in ea75e93d17

test/run-stp-tests.sh

@@ -430,10 +430,10 @@ trap "" PIPE
 gziptoany "$1" "$2" "$3" "$4" "$5" \$6 >/dev/null
 case "\$5" in
 	*media=a4* | *media=iso_a4* | *PageSize=A4*)
-		gziptoany "$1" "$2" "$3" "$4" "$5" "$root/examples/onepage-a4-300-black-1.pwg.gz"
+		gziptoany "$1" "$2" "$3" "$4" "$5" "$root/examples/onepage-a4-300-black-1.pwg"
 		;;
 	*)
-		gziptoany "$1" "$2" "$3" "$4" "$5" "$root/examples/onepage-letter-300-black-1.pwg.gz"
+		gziptoany "$1" "$2" "$3" "$4" "$5" "$root/examples/onepage-letter-300-black-1.pwg"
 		;;
 esac
 EOF