Update Devcontainers example

Author: ThomasVitale

development-environments/devcontainers/.devcontainer/devcontainer.json

@@ -3,11 +3,13 @@
 	"image": "mcr.microsoft.com/devcontainers/java",
 
 	"features": {
-    "ghcr.io/thomasvitale/devcontainers-features/flox:1": {},
+    // "ghcr.io/thomasvitale/devcontainers-features/flox:1": {},
+    "ghcr.io/devcontainers/features/nix:1": {},
 		"ghcr.io/devcontainers/features/docker-in-docker:2": {}
 	},
 
-  "postCreateCommand": "flox activate",
+  //"postCreateCommand": "flox activate",
+  "postCreateCommand": ".devcontainer/install-flox.sh && flox activate",
 
 	"customizations": {
     "vscode": {

development-environments/devcontainers/.devcontainer/install-flox.sh

@@ -0,0 +1,6 @@
+#!/bin/sh
+
+nix profile install \
+    --experimental-features "nix-command flakes" \
+    --accept-flake-config \
+    'github:flox/flox'