[1914] Update tests for the addMessage extension

As the internal data structure contains another element, we need to put
it into each test that looks into the internal data structure.

src/lib/server_common/tests/socket_requestor_test.cc

@@ -144,6 +144,7 @@ createExpectedRequest(const std::string& address,
     packet->add(Element::create("Boss"));
     packet->add(Element::create("*"));
     packet->add(createCommand("get_socket", command_args));
+    packet->add(Element::create(-1));
 
     return (packet);
 }
@@ -284,6 +285,7 @@ createExpectedRelease(const std::string& token) {
     packet->add(Element::create("Boss"));
     packet->add(Element::create("*"));
     packet->add(createCommand("drop_socket", command_args));
+    packet->add(Element::create(-1));
 
     return (packet);
 }