Remove GitHub CLI Copilot Extension installation

now depends on copilot cli, which depends on node 22, and we're still on 20

https://docs.github.com/en/copilot/how-tos/copilot-cli/install-copilot-cli

Author: kurowski

local/etc/uceap.d/devcontainer_post_create.sh

@@ -1,9 +1,4 @@
 function devcontainer_post_create() {
-	# Install GitHub CLI Copilot Extension
-	if [[ -n "$GH_TOKEN" ]] || [[ -n "$GITHUB_TOKEN" ]] ; then
-		gh extension install github/gh-copilot
-	fi
-
 	# set global ServerName so that apachectl isn't chatty
 	if [[ -n "$CODESPACE_NAME" ]]; then
 		SERVER_NAME="$CODESPACE_NAME-8080.app.github.dev"
@@ -53,4 +48,4 @@ Add the following to your `devcontainer.json` file:
 This command is the last of three that finalizes container setup when a dev container is created. It happens after `updateContentCommand` and once the dev container has been assigned to a user for the first time.
 
 Cloud services can use this command to take advantage of user specific secrets and permissions.
-'
+'