Scripts: Set errexit to catch errors

packaging/linux/buildpackage.sh

@@ -1,6 +1,7 @@
 #!/bin/bash
 # OpenRA packaging script for Linux (AppImage)
-set -e
+
+set -o errexit || exit $?
 
 command -v tar >/dev/null 2>&1 || { echo >&2 "Linux packaging requires tar."; exit 1; }
 command -v curl >/dev/null 2>&1 || command -v wget > /dev/null 2>&1 || { echo >&2 "Linux packaging requires curl or wget."; exit 1; }