[MOT] add demo citation (#4584)

configs/mot/README.md

@@ -28,6 +28,8 @@ Paddledetection implements three MOT algorithms of these two series.
 
 <div align="center">
   <img src="../../docs/images/mot16_jde.gif" width=500 />
+  <br>
+  demo resource: MOT17 dataset</div>
 </div>
 
 

configs/mot/README_cn.md

@@ -28,6 +28,8 @@ PaddleDetection实现了这两个系列的3种多目标跟踪算法。
 
 <div align="center">
   <img src="../../docs/images/mot16_jde.gif" width=500 />
+  <br>
+  视频来源：MOT17开源数据集</div>
 </div>
 
 

deploy/pptracking/README.md

@@ -8,6 +8,8 @@ PP-Tracking是基于飞桨深度学习框架的业界首个开源实时跟踪系
 
 <div width="1000" align="center">
   <img src="../../docs/images/pptracking-demo.gif"/>
+  <br>
+  视频来源：VisDrone2021, BDD100K开源数据集</div>
 </div>
 
 ### 一、快速开始