docs: update wechat qr code, test=document_fix

README_ch.md

@@ -37,7 +37,7 @@ Res2Net200_vd预训练模型Top-1精度高达85.1%。
 * 您可以扫描下面的微信群二维码， 加入PaddleClas 微信交流群。获得更高效的问题答疑，与各行各业开发者充分交流，期待您的加入。
 
 <div align="center">
-<img src="./docs/images/wx_group.png"  width = "200" />
+<img src="https://user-images.githubusercontent.com/12560511/150500411-fdb27d17-0c50-4ac1-a484-fb4a9c2454b3.jpg"  width = "200" />
 </div>
 
 ## 快速体验

README_en.md

@@ -8,7 +8,7 @@ PaddleClas is an image recognition toolset for industry and academia, helping us
 
 **Recent updates**
 
-- 2021.09.17 Add PP-LCNet series model developed by PaddleClas, these models show strong competitiveness on Intel CPUs. 
+- 2021.09.17 Add PP-LCNet series model developed by PaddleClas, these models show strong competitiveness on Intel CPUs.
 For the introduction of PP-LCNet, please refer to [paper](https://arxiv.org/pdf/2109.15099.pdf) or [PP-LCNet model introduction](docs/en/models/PP-LCNet_en.md). The metrics and pretrained model are available [here](docs/en/ImageNet_models_en.md).
 
 - 2021.06.29 Add Swin-transformer series model，Highest top1 acc on ImageNet1k dataset reaches 87.2%, training, evaluation and inference are all supported. Pretrained models can be downloaded [here](docs/en/models/models_intro_en.md).
@@ -41,7 +41,7 @@ Four sample solutions are provided, including product recognition, vehicle recog
 * You can also scan the QR code below to join the PaddleClas WeChat group to get more efficient answers to your questions and to communicate with developers from all walks of life. We look forward to hearing from you.
 
 <div align="center">
-<img src="./docs/images/wx_group.png"  width = "200" />
+<img src="https://user-images.githubusercontent.com/12560511/150500411-fdb27d17-0c50-4ac1-a484-fb4a9c2454b3.jpg"  width = "200" />
 </div>
 
 ## Quick Start