Fixed CI badge URL (#7337)

README.md

@@ -252,7 +252,7 @@ questions and get our support.
 [docker-server-image-url]: https://hub.docker.com/r/cvat/server
 [docker-ui-pulls-img]: https://img.shields.io/docker/pulls/cvat/ui.svg?style=flat-square&label=UI%20pulls
 [docker-ui-image-url]: https://hub.docker.com/r/cvat/ui
-[ci-img]: https://github.com/opencv/cvat/workflows/CI/badge.svg?branch=develop
+[ci-img]: https://github.com/opencv/cvat/actions/workflows/main.yml/badge.svg?branch=develop
 [ci-url]: https://github.com/opencv/cvat/actions
 [gitter-img]: https://img.shields.io/gitter/room/opencv-cvat/public?style=flat
 [gitter-url]: https://gitter.im/opencv-cvat/public