add --init runArg to r definition (#1049)

Author: joshspicer

containers/r/.devcontainer/devcontainer.json

@@ -37,8 +37,9 @@
 	// Uncomment to use Docker from inside the container. See https://aka.ms/vscode-remote/samples/docker-from-docker.
 	// "mounts": [ "source=/var/run/docker.sock,target=/var/run/docker.sock,type=bind" ],
 
-	// Uncomment when using a ptrace-based debugger like C++, Go, and Rust
-	// "runArgs": [ "--cap-add=SYS_PTRACE", "--security-opt", "seccomp=unconfined" ],
+	// Replace runArgs below when using a ptrace-based debugger like C++, Go, and Rust
+	// "runArgs": [ "--init", "--cap-add=SYS_PTRACE", "--security-opt", "seccomp=unconfined" ],
+	"runArgs": [ "--init" ],
 
 	// Comment out connect as root instead. More info: https://aka.ms/vscode-remote/containers/non-root.
 	"remoteUser": "vscode"