Add devcontainer badge in README.md

README.md

@@ -22,6 +22,7 @@ limitations under the License.
 [![codecov](https://codecov.io/gh/apache/celix/branch/master/graph/badge.svg)](https://codecov.io/gh/apache/celix)
 [![Coverity Scan Build Status](https://scan.coverity.com/projects/6685/badge.svg)](https://scan.coverity.com/projects/6685)
 [![Gitpod ready-to-code](https://img.shields.io/badge/Gitpod-ready--to--code-blue?logo=gitpod)](https://gitpod.io/#https://github.com/apache/celix)
+[![Open in Dev Containers](https://img.shields.io/static/v1?label=Dev%20Containers&message=Open&color=blue&logo=visualstudiocode)](https://vscode.dev/redirect?url=vscode://ms-vscode-remote.remote-containers/cloneInVolume?url=https://github.com/apache/celix)
 
 Apache Celix is a framework for C and C++14 to develop dynamic modular software applications using component 
 and in-process service-oriented programming.