lorawan: Use mock EventQueue

Previously we were using a real event queue with the lorawantimer unit
tests. This caused an MBED_ASSERT to fail, as the real queue would check
that the timer_id returned would be non-zero. The call_in stub returns 0
or null values, so was failing. Use the mock EventQueue instead.

Author: Patater

connectivity/lorawan/tests/UNITTESTS/features/lorawan/lorawantimer/CMakeLists.txt

@@ -19,11 +19,12 @@ target_sources(${TEST_NAME}
 
 target_link_libraries(${TEST_NAME}
     PRIVATE
+        mbed-fakes-event-queue
         mbed-headers-base
-        mbed-headers-events
         mbed-headers-platform
         mbed-headers-lorawan
         mbed-stubs
+        mbed-stubs-events
         mbed-stubs-headers
         gmock_main
 )