cmd/relui: fix private Gerrit URL

Got the path wrong.

For golang/go#53799.

Change-Id: I576c2991d5297da11307cb033cb3ad3125986f8f
Reviewed-on: https://go-review.googlesource.com/c/build/+/417592
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Heschi Kreinick <heschi@google.com>
Run-TryBot: Heschi Kreinick <heschi@google.com>
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>

cmd/relui/main.go

@@ -141,7 +141,7 @@ func main() {
 	buildTasks := &relui.BuildReleaseTasks{
 		GerritHTTPClient: oauth2.NewClient(ctx, creds.TokenSource),
 		GerritURL:        "https://go.googlesource.com/go",
-		PrivateGerritURL: "https://team.googlesource.com/go-private",
+		PrivateGerritURL: "https://team.googlesource.com/golang/go-private",
 		CreateBuildlet:   coordinator.CreateBuildlet,
 		GCSClient:        gcsClient,
 		ScratchURL:       *scratchFilesBase,