Update test action badge

README.md

@@ -1,6 +1,6 @@
 # Read Me
 
-![Test](https://github.com/Kozea/Radicale/workflows/Test/badge.svg?branch=master)
+[![Test](https://github.com/Kozea/Radicale/actions/workflows/test.yml/badge.svg?branch=master)](https://github.com/Kozea/Radicale/actions/workflows/test.yml)
 [![Coverage Status](https://coveralls.io/repos/github/Kozea/Radicale/badge.svg?branch=master)](https://coveralls.io/github/Kozea/Radicale?branch=master)
 
 Radicale is a free and open-source CalDAV and CardDAV server.