Simplify logical process

mirai-core/src/commonMain/kotlin/net.mamoe.mirai/network/protocol/tim/packet/action/UploadImage.kt

@@ -36,17 +36,17 @@ class OverFileSizeMaxException : IllegalStateException()
  */
 suspend fun Group.uploadImage(image: ExternalImage): ImageId = withSession {
     val userContext = coroutineContext
-    GroupImageIdRequestPacket(bot.qqAccount, internalId, image, sessionKey)
-        .sendAndExpectAsync<GroupImageIdRequestPacket.Response, Unit> {
+    val response = GroupImageIdRequestPacket(bot.qqAccount, internalId, image, sessionKey).sendAndExpect<GroupImageIdRequestPacket.Response>()
+
     withContext(userContext) {
-                when (it) {
+        when (response) {
             is GroupImageIdRequestPacket.Response.RequireUpload -> httpClient.postImage(
                 htcmd = "0x6ff0071",
                 uin = bot.qqAccount,
                 groupId = GroupId(id),
                 imageInput = image.input,
                 inputSize = image.inputSize,
-                        uKeyHex = it.uKey.toUHexString("")
+                uKeyHex = response.uKey.toUHexString("")
             )
 
             is GroupImageIdRequestPacket.Response.AlreadyExists -> {
@@ -55,8 +55,8 @@ suspend fun Group.uploadImage(image: ExternalImage): ImageId = withSession {
             is GroupImageIdRequestPacket.Response.OverFileSizeMax -> throw OverFileSizeMaxException()
         }
     }
-        }.join()
-    image.groupImageId
+
+    return image.groupImageId
 }
 
 /**