Update badge.
:align: center
:alt: law logo
-.. image:: https://img.shields.io/travis/riga/law/master.svg?style=flat
- :target: https://travis-ci.org/riga/law
+.. image:: https://github.com/riga/law/workflows/Lint%20and%20test/badge.svg
+ :target: https://github.com/riga/law/actions?query=workflow%3A%22Lint+and+test%22
:alt: Build status
.. image:: https://readthedocs.org/projects/law/badge/?version=latest
