ci: k8s: rke2: Use sudo to call systemd

Otherwise we'll face the following error:
```
Failed to enable unit: Interactive authentication required.
```

Signed-off-by: Fabiano Fidêncio <fabiano.fidencio@intel.com>
(cherry picked from commit 07a6e63a6b)

tests/gha-run-k8s-common.sh

@@ -168,7 +168,7 @@ function deploy_k3s() {
 function deploy_rke2() {
 	curl -sfL https://get.rke2.io | sudo sh -
 
-	systemctl enable --now rke2-server.service
+	sudo systemctl enable --now rke2-server.service
 
 	# This is an arbitrary value that came up from local tests
 	sleep 120s