8023326: [TESTBUG] java/net/CookieHandler/LocalHostCookie.java misplaced try/finally

Summary: amended test to be more robust to set of potential exceptions thrown
Reviewed-by: chegar, khazra

test/java/net/CookieHandler/LocalHostCookie.java

@@ -72,7 +72,9 @@ public class LocalHostCookie {
                 }
             }
         } finally {
-            s.stopServer();
+            if (s != null) {
+                s.stopServer();
+            }
         }
     }
 
@@ -96,7 +98,9 @@ public class LocalHostCookie {
         }
 
         public void stopServer() {
-            server.stop(0);
+            if (server != null) {
+                server.stop(0);
+            }
         }
     }