add docker installation documentation on a separate new `.md` file and link it on the readme PS: there is already a PR (https://github.com/Cloud-CV/EvalAI/pull/4450) opened. Please add a video for installation as well so that contributors can verify
add docker installation documentation on a separate new
.mdfile and link it on the readmePS: there is already a PR (#4450) opened. Please add a video for installation as well so that contributors can verify