fix: support jdk11 attach exception

Author: ReaJason

packer/src/main/java/com/reajason/javaweb/packer/jar/attach/Attacher.java

@@ -57,7 +57,17 @@ public static void main(String[] args) throws Exception {
             Attacher.attach(args[0]);
         } catch (Exception e) {
             if (!e.getMessage().equals("0")) {
-                throw e;
+                Throwable cause = e.getCause();
+                if (cause != null) {
+                    if (!cause.getMessage().equals("0")) {
+                        cause = e.getCause();
+                        if (cause != null) {
+                            if (!cause.getMessage().equals("0")) {
+                                throw e;
+                            }
+                        }
+                    }
+                }
             }
         }
         System.out.println("ok");