Add test for auth violations during reconnect

Introduce a new test case to reproduce issue #1320, focusing on handling authorization violations during reconnections. It also makes the `closeSocketLock` in `NatsConnection` package-private to facilitate testing.

Author: ajax-surovskyi-y

src/test/java/io/nats/client/impl/AuthViolationDuringReconnect.java

@@ -66,6 +66,7 @@ private static Runnable waitCloseSocket(NatsConnection nc) {
 
     private static void restartServer(AtomicReference<NatsTestServer> ts, int port) {
         try {
+            System.out.println("Restarting server");
             ts.get().shutdown();
             ts.set(new NatsTestServer(new String[]{"--auth", "1234", "-m", "8222"}, port, false));
         } catch (Exception e) {