[23.0] fix vendor.mod: add hashicorp/go-multierror as direct dependency

commit 59118bff500fc0d95d0560a9788735a8d89568ce made this a direct
dependency (previously it was indirect). That commit was part of an
advisory, and didn't run the vendor validation check because of that.

This patch fixes the vendor.mod to unblock CI in this branch.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

vendor.mod

@@ -42,6 +42,7 @@ require (
 	github.com/gorilla/mux v1.8.0
 	github.com/hashicorp/go-immutable-radix v1.3.1
 	github.com/hashicorp/go-memdb v1.3.2
+	github.com/hashicorp/go-multierror v1.1.1
 	github.com/hashicorp/memberlist v0.4.0
 	github.com/hashicorp/serf v0.8.5
 	github.com/imdario/mergo v0.3.12
@@ -125,7 +126,6 @@ require (
 	github.com/grpc-ecosystem/grpc-gateway v1.16.0 // indirect
 	github.com/hashicorp/errwrap v1.1.0 // indirect
 	github.com/hashicorp/go-msgpack v0.5.5 // indirect
-	github.com/hashicorp/go-multierror v1.1.1 // indirect
 	github.com/hashicorp/go-sockaddr v1.0.2 // indirect
 	github.com/hashicorp/golang-lru v0.5.4 // indirect
 	github.com/inconshreveable/mousetrap v1.0.1 // indirect