Initialize StatelessResetToken in QuicTimeWaitListManagerTest.

Default-initialize the `stateless_reset_token_` member to prevent potential uninitialized value issues.

PiperOrigin-RevId: 921914995

quiche/quic/core/quic_time_wait_list_manager_test.cc

diff --git a/quiche/quic/core/quic_time_wait_list_manager_test.cc b/quiche/quic/core/quic_time_wait_list_manager_test.cc
index 5646440..9c252f6 100644
--- a/quiche/quic/core/quic_time_wait_list_manager_test.cc
+++ b/quiche/quic/core/quic_time_wait_list_manager_test.cc
@@ -73,7 +73,7 @@
   }
 
  private:
-  StatelessResetToken stateless_reset_token_;
+  StatelessResetToken stateless_reset_token_ = {};
   QuicConnectionId connection_id_;
 };