Add move-only handler tests

test/beast/websocket/handshake.cpp

@@ -484,6 +484,14 @@ public:
             "permessage-deflate");
     }
 
+    void
+    testMoveOnly()
+    {
+        boost::asio::io_context ioc;
+        stream<test::stream> ws{ioc};
+        ws.async_handshake("", "", move_only_handler{});
+    }
+
     void
     run() override
     {
@@ -491,6 +499,7 @@ public:
         testExtRead();
         testExtWrite();
         testExtNegotiate();
+        testMoveOnly();
     }
 };