Use default java instead of hardcoded java

Signed-off-by: Lixfel <agga-games@gmx.de>

src/de/steamwar/bungeecore/Node.java

@@ -74,7 +74,7 @@ public abstract class Node {
     public abstract double getLoad();
 
     protected void constructServerstart(File directory, List<String> cmd, String serverJar, String worldDir, String levelName, int port, String xmx, String... dParams) {
-        cmd.add("/usr/lib/jvm/java-16-openj9-amd64/bin/java");
+        cmd.add("java");
 
         for(String param : dParams){
             cmd.add("-D" + param);