Swap QUIC_LOG to QUIC_DLOG.

"Invalid SNI" indicates a malformed request and isn't actionable in prod, but may be useful for debugging sometimes.

PiperOrigin-RevId: 434813348

quic/core/tls_server_handshaker.cc

diff --git a/quic/core/tls_server_handshaker.cc b/quic/core/tls_server_handshaker.cc
index 00db13d..53a8bd8 100644
--- a/quic/core/tls_server_handshaker.cc
+++ b/quic/core/tls_server_handshaker.cc
@@ -1080,7 +1080,7 @@
   if (!QuicHostnameUtils::IsValidSNI(hostname)) {
     // TODO(b/151676147): Include this error string in the CONNECTION_CLOSE
     // frame.
-    QUIC_LOG(ERROR) << "Invalid SNI provided: \"" << hostname << "\"";
+    QUIC_DLOG(ERROR) << "Invalid SNI provided: \"" << hostname << "\"";
     return false;
   }
   return true;