Add GH CLI to devcontainer, use the customizations field, turn on dependabot for devcontainers.

.devcontainer/devcontainer.json

@@ -2,9 +2,17 @@
   "name": "TypeScript Website codespace",
   "dockerFile": "Dockerfile",
 
+  "features": {
+    "ghcr.io/devcontainers/features/github-cli": "latest",
+  },
+
   // Set *default* container specific settings.json values on container create.
-  "settings": {
-    "terminal.integrated.shell.linux": "/bin/bash"
+  "customizations": {
+    "vscode": {
+      "settings": {
+        "terminal.integrated.shell.linux": "/bin/bash"
+      }
+    }
   },
 
   "forwardPorts": [8000],

.github/dependabot.yml

@@ -1,7 +1,8 @@
 # To get started with Dependabot version updates, you'll need to specify which
 # package ecosystems to update and where the package manifests are located.
-# Please see the documentation for all configuration options:
+# Please see the documentation for more information:
 # https://docs.github.com/github/administering-a-repository/configuration-options-for-dependency-updates
+# https://containers.dev/guide/dependabot
 
 version: 2
 updates:
@@ -13,3 +14,9 @@ updates:
       github-actions:
         patterns:
           - '*'
+
+  - package-ecosystem: 'devcontainers'
+    directory: '/'
+    schedule:
+      interval: weekly
+