Add codespace defaults

.devcontainer/devcontainer.json

@@ -0,0 +1,9 @@
+{
+  "name": "Dependency Review Action",
+  "image": "mcr.microsoft.com/devcontainers/typescript-node:18",
+  "postCreateCommand": "npm install",
+  "remoteUser": "node",
+  "features": {
+    "ghcr.io/devcontainers/features/ruby:1": {}
+  }
+}