Update workflows (#6427)

* Workflow updates

* quotes fix

* best to weights fix

README.md

@@ -63,7 +63,7 @@ See the [YOLOv5 Docs](https://docs.ultralytics.com) for full documentation on tr
 <summary>Install</summary>
 
 Clone repo and install [requirements.txt](https://github.com/ultralytics/yolov5/blob/master/requirements.txt) in a
-[**Python>=3.6.0**](https://www.python.org/) environment, including
+[**Python>=3.7.0**](https://www.python.org/) environment, including
 [**PyTorch>=1.7**](https://pytorch.org/get-started/locally/).
 
 ```bash