Remove redundant stop() calls from LiveReloadServerTests

spring-boot-project/spring-boot-devtools/src/test/java/org/springframework/boot/devtools/livereload/LiveReloadServerTests.java

 /*
- * Copyright 2012-2019 the original author or authors.
+ * Copyright 2012-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -89,7 +89,6 @@ class LiveReloadServerTests {
 		LiveReloadWebSocketHandler handler = connect();
 		this.server.triggerReload();
 		Thread.sleep(200);
-		this.server.stop();
 		assertThat(handler.getMessages().get(0)).contains("http://livereload.com/protocols/official-7");
 		assertThat(handler.getMessages().get(1)).contains("command\":\"reload\"");
 	}
@@ -100,7 +99,6 @@ class LiveReloadServerTests {
 		handler.sendMessage(new PingMessage());
 		Thread.sleep(200);
 		assertThat(handler.getPongCount()).isEqualTo(1);
-		this.server.stop();
 	}
 
 	@Test