race condition in subscribe response output

[oleg8000]

Some times sync-response shown first if launch gnmic with next args ' --insecure subscribe --mode stream --stream-mode on-change --path '/*''
Looks like because of 'go' here

gnmic/pkg/app/collector.go

Line 102 in a778c27

go a.Export(ctx, rsp.Response, m, outs...)