Merge pull request cli#13033 from Lslightly/13001-fix-err-data-race-and-heap-alloc

define err in go func instead of use err defined in outer scope

Author: williammartin

internal/codespaces/portforwarder/port_forwarder.go

@@ -276,7 +276,7 @@ func (fwd *CodespacesPortForwarder) UpdatePortVisibility(ctx context.Context, re
 	done := make(chan error)
 	go func() {
 		// Connect to the tunnel
-		err = fwd.connection.Connect(ctx)
+		err := fwd.connection.Connect(ctx)
 		if err != nil {
 			done <- fmt.Errorf("connect failed: %v", err)
 			return