Fix bad return value

scripts/install-spigot.sh

@@ -10,11 +10,12 @@ fi
 IFS=',' read -r -a versions <<< "$REV"
 
 for ver in "${versions[@]}"; do
+  ARTIFACT="spigot-${ver}.jar"
+
   echo "Attempting to locate $ver..."
 
   mvn -q org.apache.maven.plugins:maven-dependency-plugin:3.9.0:get -Dartifact=org.spigotmc:spigot:${ver}-R0.1-SNAPSHOT
 
-  ARTIFACT="spigot-${ver}.jar"
   if [ "$?" -eq 0 ] && [[ "$SERVER_REQUIRED" == "false" || -e "/build/$ARTIFACT" ]]; then
     echo "Located spigot $ver successfully"
   else