Make QUIC interop runner print version

This is test-only code.

PiperOrigin-RevId: 347633893
Change-Id: I432148325ed13176efcc556a99dcca15a64e47bd
diff --git a/quic/tools/quic_client_interop_test_bin.cc b/quic/tools/quic_client_interop_test_bin.cc
index 4ca2a50..3c841da 100644
--- a/quic/tools/quic_client_interop_test_bin.cc
+++ b/quic/tools/quic_client_interop_test_bin.cc
@@ -381,6 +381,8 @@
   CHECK(version.IsKnown());
   QuicEnableVersion(version);
 
+  std::cout << "Attempting interop with version " << version << std::endl;
+
   // Build the client, and try to connect.
   QuicSocketAddress addr = tools::LookupAddress(dns_host, absl::StrCat(port));
   if (!addr.IsInitialized()) {