[json] Pick part of JSON schema with more matching properties

From https://github.com/microsoft/vscode-remote-release/issues/4806: ```json { "dockerComposeFile": "docker-compose.yml", "service": "devcontainer", "workspaceFolder": "/workspace", "containerEnv": { "HTTP_PROXY": "${localEnv:HTTP_PROXY}", "HTTPS_PROXY": "${localEnv:HTTPS_PROXY}", "DOCKER_CWD": "${localWorkspaceFolder}" }, } ``` Shows warnings on `"dockerComposeFile"` and `"service"` and asks for `"build"` to be added when the smaller change would be to remove `"containerEnv"`.