chore: fix github codesapce init (#11590)

.devcontainer/setup-user.sh

@@ -1,9 +1,9 @@
 set -e
 
+npm install -g @withgraphite/graphite-cli@stable
+
 if [ -v GRAPHITE_TOKEN ];then
     gt auth --token $GRAPHITE_TOKEN
 fi
 
-git fetch origin canary:canary --depth=1
-git branch canary -t origin/canary
 gt init --trunk canary