cmd/osbuild-worker-executor: import verbatim from mvo5/oaas

This commit imports the repository https://github.com/mvo5/oaas
without keeping the history. The history is largely unimportant
and can be looked up in https://github.com/mvo5/oaas/commits/main
if needed.

cmd/osbuild-worker-executor/handler_root.go

@@ -0,0 +1,16 @@
+package main
+
+import (
+	"net/http"
+
+	"github.com/sirupsen/logrus"
+)
+
+func handleRoot(logger *logrus.Logger, _ *Config) http.Handler {
+	return http.HandlerFunc(
+		func(w http.ResponseWriter, r *http.Request) {
+			// we just return ok here
+			logger.Info("/ handler called")
+		},
+	)
+}