Bound setup Helm wait behavior

Use hook-only wait mode for Fleet chart install in
`dev/setup-fleet` to avoid Helm watcher hangs during setup.

Because in Helm v4, wait without a mode can use a watcher strategy that
keeps tracking non-hook resources and can stay stuck in pending-install
even after pods are already healthy.

Author: thardeck

dev/setup-fleet

@@ -36,7 +36,7 @@ if [ -n "$shards_json" ]; then
   done
 fi
 
-helm -n cattle-fleet-system upgrade --install --create-namespace --wait --reset-values \
+helm -n cattle-fleet-system upgrade --install --create-namespace --wait=hookOnly --reset-values \
   --set apiServerCA="$ca" \
   --set apiServerURL="$server" \
   $shards_settings \