metropolis/curator: log warning if cluster configuration cannot be loaded

Change-Id: I4ad520d7545fe88d0db85a223f3a2e6d51e05136
Reviewed-on: https://review.monogon.dev/c/monogon/+/3466
Reviewed-by: Lorenz Brun <lorenz@monogon.tech>
Tested-by: Jenkins CI
diff --git a/metropolis/node/core/curator/impl_leader_management.go b/metropolis/node/core/curator/impl_leader_management.go
index a7eaf5f..494271f 100644
--- a/metropolis/node/core/curator/impl_leader_management.go
+++ b/metropolis/node/core/curator/impl_leader_management.go
@@ -17,6 +17,7 @@
 	"source.monogon.dev/metropolis/node/core/rpc"
 	apb "source.monogon.dev/metropolis/proto/api"
 	cpb "source.monogon.dev/metropolis/proto/common"
+	"source.monogon.dev/osbase/supervisor"
 )
 
 type leaderManagement struct {
@@ -125,6 +126,8 @@
 	cl, err := clusterLoad(ctx, l.leadership)
 	if err == nil {
 		resp.ClusterConfiguration, _ = cl.proto()
+	} else {
+		supervisor.Logger(ctx).Errorf("Could not load cluster configuration: %v", err)
 	}
 
 	return resp, nil