devcontainer: update go version, use features

From what I've read, we want the base image to be smaller, with more
of the added functionality in features.  We can build a bigger image
with the features, but that should be an image for devcontainers.

Also it seems that devcontainer tooling will cache the image with the
features - maybe giving similar results to if we had built a more
complete image.

.devcontainer/devcontainer.json

@@ -3,7 +3,8 @@
     "name": "Kops environment from dev container",
     // Image to pull when not building from scratch. See .devcontainer/build/devcontainer.json
     // and .github/devcontainer-build-and-push.yml for the instructions on how this image is built
-    "image": "registry.k8s.io/build-image/kube-cross:v1.29.0-go1.21.3-bullseye.0",
+    "image": "debian:bullseye",
+    // "image": "registry.k8s.io/build-image/kube-cross:v1.30.0-go1.22.0-bullseye.0",
     // Setup the go environment and mount into the dev container at the expected location
     "workspaceFolder": "/go/src/k8s.io/kops",
     "workspaceMount": "source=${localWorkspaceFolder},target=/go/src/k8s.io/kops,type=bind,consistency=cached",
@@ -17,10 +18,21 @@
     "otherPortsAttributes": {
         "onAutoForward": "silent"
     },
-    "remoteUser": "root"
+    "remoteUser": "root",
     // Configure tool-specific properties.
     // "customizations": {
     // },
     // Use 'forwardPorts' to make a list of ports inside the container available locally.
     // "forwardPorts": [],
-}
+
+    // Features to add to the dev container. More info: https://containers.dev/features.
+	"features": {
+		"ghcr.io/devcontainers/features/github-cli:1": {
+			"installDirectlyFromGitHubRelease": true,
+			"version": "latest"
+		},
+		"ghcr.io/devcontainers/features/go:1": {
+			"version": "latest"
+		}
+	}
+}

.devcontainer/setup.sh

@@ -17,6 +17,7 @@
 set -eux
 
 # Copies over welcome message
+mkdir -p /usr/local/etc/vscode-dev-containers/
 cp .devcontainer/welcome-message.txt /usr/local/etc/vscode-dev-containers/first-run-notice.txt
 
 git remote add upstream https://github.com/kubernetes/kops.git