Fix memleak only happening on fuzzer

See https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=6026

Credit to oss-fuzz

src/server/ua_server_binary.c

@@ -455,6 +455,7 @@ processMSG(UA_Server *server, UA_SecureChannel *channel,
 
     #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
     // set the authenticationToken from the create session request to help fuzzing cover more lines
+    UA_NodeId_deleteMembers(&requestHeader->authenticationToken);
     if(!UA_NodeId_isNull(&unsafe_fuzz_authenticationToken))
         UA_NodeId_copy(&unsafe_fuzz_authenticationToken, &requestHeader->authenticationToken);
     #endif