runtime: Add make vendor

Let's add this target so we can actually enforce, as part of the static
checks (which will be added in a follow-up commit), that our vendored go
code is up-to-date.

Related: #2159

Signed-off-by: Fabiano Fidêncio <fidencio@redhat.com>

src/runtime/Makefile

@@ -653,6 +653,9 @@ handle_vendor:
 	go mod vendor
 	go mod verify
 
+vendor: handle_vendor
+	./hack/tree_status.sh
+
 clean:
 	$(QUIET_CLEAN)rm -f \
 		$(CONFIGS) \

src/runtime/hack/tree_status.sh

@@ -0,0 +1,18 @@
+#!/usr/bin/env bash
+#
+# Copyright 2021 Red Hat Inc.
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+set -e
+
+STATUS=$(git status --porcelain)
+if [[ -z $STATUS ]]; then
+    echo "tree is clean"
+else
+    echo "tree is dirty, please commit all changes"
+    echo ""
+    echo "$STATUS"
+    git diff
+    exit 1
+fi