fix: The "name" is not a mandatory parameter for joining the group interface.

Author: rchht

README-CN.md

@@ -11,12 +11,12 @@ RongCloud IM Server SDK in Java.
     <dependency>
         <groupId>cn.rongcloud.im</groupId>
         <artifactId>server-sdk-java</artifactId>
-        <version>4.0.8</version>
+        <version>4.0.9</version>
     </dependency>
 ```
    * Gradle
 ```
-    compile group: 'cn.rongcloud.im', name: 'server-sdk-java', version: '4.0.8'
+    compile group: 'cn.rongcloud.im', name: 'server-sdk-java', version: '4.0.9'
    
 ```
    * 基于源码 Meavn 打包构建

README.md

@@ -10,12 +10,12 @@ RongCloud IM Server SDK in Java.
     <dependency>
         <groupId>cn.rongcloud.im</groupId>
         <artifactId>server-sdk-java</artifactId>
-        <version>4.0.8</version>
+        <version>4.0.9</version>
     </dependency>
 ```
 * Gradle
 ```
-    compile group: 'cn.rongcloud.im', name: 'server-sdk-java', version: '4.0.8'
+    compile group: 'cn.rongcloud.im', name: 'server-sdk-java', version: '4.0.9'
 ```
 * Build from source
 ```

pom.xml

@@ -6,7 +6,7 @@
 
     <groupId>cn.rongcloud.im</groupId>
     <artifactId>server-sdk-java</artifactId>
-    <version>4.0.8</version>
+    <version>4.0.9</version>
     <packaging>jar</packaging>
     <name>RongCloud IM Server SDK</name>
     <description>

src/main/resources/jsonsource/group/api.json

@@ -147,8 +147,7 @@
 				"members": [{
 					"id": "memberId01"
 				}],
-				"id": "10001",
-				"name": "TestGroup"
+				"id": "10001"
 			}
 		},
 		"response":{