docs: fix test workflow badge (#1512)

Author: dalryan

README.md

@@ -1,6 +1,6 @@
 ![Ginkgo](https://onsi.github.io/ginkgo/images/ginkgo.png)
 
-[![test](https://github.com/onsi/ginkgo/workflows/test/badge.svg?branch=master)](https://github.com/onsi/ginkgo/actions?query=workflow%3Atest+branch%3Amaster) | [Ginkgo Docs](https://onsi.github.io/ginkgo/)
+[![test](https://github.com/onsi/ginkgo/actions/workflows/test.yml/badge.svg?branch=master)](https://github.com/onsi/ginkgo/actions?query=workflow%3Atest+branch%3Amaster) | [Ginkgo Docs](https://onsi.github.io/ginkgo/)
 
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