RequestMessageTest.cc: disable vehicle gimbal controller on this test:

As it also sends request messages and it collides with the
requests of this test

src/Vehicle/RequestMessageTest.cc

@@ -38,6 +38,9 @@ void RequestMessageTest::_testCaseWorker(TestCase_t& testCase)
     MultiVehicleManager*    vehicleMgr  = qgcApp()->toolbox()->multiVehicleManager();
     Vehicle*                vehicle     = vehicleMgr->activeVehicle();
     
+    // Gimbal controller sends message requests when receiving heartbeats, trying to find a gimbal, and it messes with this test so we disable it
+    vehicle->deleteGimbalController();
+
     _mockLink->clearReceivedMavCommandCounts();
     _mockLink->setRequestMessageFailureMode(testCase.failureMode);