Add Group.setEssenceMessage(MessageChain)

mirai-core-api/src/commonMain/kotlin/contact/Group.kt

@@ -178,7 +178,19 @@ public interface Group : Contact, CoroutineScope {
     @JvmBlockingBridge
     public suspend fun setEssenceMessage(source: MessageSource): Boolean
 
-    public companion object
+    public companion object {
+        /**
+         * 将一条消息设置为群精华消息, 需要管理员或群主权限.
+         * 操作成功返回 `true`.
+         *
+         * @throws PermissionDeniedException 没有权限时抛出
+         *
+         * @see Group.setEssenceMessage
+         * @since 2.2
+         */
+        @JvmBlockingBridge
+        public suspend fun Group.setEssenceMessage(chain: MessageChain): Boolean = setEssenceMessage(chain.source)
+    }
 }
 
 /**