test: declare MockPeerServer move members (rule of 5)

Author: bburda

src/ros2_medkit_gateway/test/test_plugin_context_aggregation.cpp

@@ -102,6 +102,8 @@ class MockPeerServer {
 
   MockPeerServer(const MockPeerServer &) = delete;
   MockPeerServer & operator=(const MockPeerServer &) = delete;
+  MockPeerServer(MockPeerServer &&) = delete;
+  MockPeerServer & operator=(MockPeerServer &&) = delete;
 
   httplib::Server & server() {
     if (!server_) {