Properly forward exit 1 code from the paper root command

This is so the CI server can pick up when applying patches fails,
and mark the build as a failure.

scripts/paperclip.sh

@@ -19,4 +19,4 @@ echo ""
 echo ""
 echo "Build success!"
 echo "Copied final jar to $(cd "$basedir" && pwd -P)/paperclip.jar"
-)
+) || exit 1