Fix MoViNet Colab link.

PiperOrigin-RevId: 373161185

official/vision/beta/projects/movinet/README.md

 # Mobile Video Networks (MoViNets)
 
-[![Open In Colab](https://colab.research.google.com/assets/colab-badge.svg)](https://colab.research.google.com/github/tensorflow/models/tree/master/official/vision/beta/projects/movinet/movinet_tutorial.ipynb)
+[![Open In Colab](https://colab.research.google.com/assets/colab-badge.svg)](https://colab.research.google.com/github/tensorflow/models/blob/master/official/vision/beta/projects/movinet/movinet_tutorial.ipynb)
 [![TensorFlow Hub](https://img.shields.io/badge/TF%20Hub-Models-FF6F00?logo=tensorflow)](https://tfhub.dev/google/collections/movinet)
 [![Paper](http://img.shields.io/badge/Paper-arXiv.2103.11511-B3181B?logo=arXiv)](https://arxiv.org/abs/2103.11511)