Update README.md

Author: tpadioleau

README.md

@@ -9,6 +9,7 @@ SPDX-License-Identifier: MIT
 [![Nightly early integration](https://github.com/CExA-project/ddc/actions/workflows/early_integration.yaml/badge.svg?event=schedule)](https://github.com/CExA-project/ddc/actions/workflows/early_integration.yaml)
 [![Nightly tests on Ubuntu](https://github.com/CExA-project/ddc/actions/workflows/tests-ubuntu.yaml/badge.svg?event=schedule)](https://github.com/CExA-project/ddc/actions/workflows/tests-ubuntu.yaml)
 [![Nightly tests on macOS](https://github.com/CExA-project/ddc/actions/workflows/tests-macos.yaml/badge.svg?event=schedule)](https://github.com/CExA-project/ddc/actions/workflows/tests-macos.yaml)
+[![Nightly tests on Windows](https://github.com/CExA-project/ddc/actions/workflows/tests-windows.yaml/badge.svg?event=schedule)](https://github.com/CExA-project/ddc/actions/workflows/tests-windows.yaml)
 [![Pages](https://github.com/CExA-project/ddc/actions/workflows/pages.yaml/badge.svg)](https://github.com/CExA-project/ddc/actions/workflows/pages.yaml)
 
 See <https://ddc.mdls.fr/>