fix(netxlite): http3 transport needs logging by default (#492)

Adapt other places where it was not using a logger to either choose
a reasonable logger or disable logging for backwards compat.

See https://github.com/ooni/probe/issues/1591

internal/engine/netx/httptransport/http3transport.go

@@ -10,7 +10,15 @@ import (
 //
 // New code should use netxlite.NewHTTP3Transport instead.
 func NewHTTP3Transport(config Config) RoundTripper {
-	return netxlite.NewHTTP3Transport(
+	// Rationale for using NoLogger here: previously this code did
+	// not use a logger as well, so it's fine to keep it as is.
+	return netxlite.NewHTTP3Transport(&NoLogger{},
 		netxlite.NewQUICDialerFromContextDialerAdapter(config.QUICDialer),
 		config.TLSConfig)
 }
+
+type NoLogger struct{}
+
+func (*NoLogger) Debug(message string) {}
+
+func (*NoLogger) Debugf(format string, v ...interface{}) {}