Little cmake and tests refactor

Change from spdlog_ex to const spdlog_ex& got rid of the GCC8 warning.

tests/CMakeLists.txt

@@ -1,5 +1,5 @@
 project(spdlog-utests CXX)
-enable_testing()
+
 find_package(Threads REQUIRED)
 
 set(SPDLOG_UTESTS_SOURCES
@@ -7,18 +7,23 @@ set(SPDLOG_UTESTS_SOURCES
     file_helper.cpp
     file_log.cpp
     test_misc.cpp
-	test_pattern_formatter.cpp
+    test_pattern_formatter.cpp
     test_async.cpp
     includes.h
     registry.cpp
     test_macros.cpp
     utils.cpp
     utils.h
-    main.cpp test_mpmc_q.cpp)
+    main.cpp
+    test_mpmc_q.cpp
+    test_sink.h
+)
 
 add_executable(${PROJECT_NAME} ${SPDLOG_UTESTS_SOURCES})
 target_link_libraries(${PROJECT_NAME} PRIVATE Threads::Threads)
 target_link_libraries(${PROJECT_NAME} PRIVATE spdlog::spdlog)
 
-add_test(NAME ${PROJECT_NAME} COMMAND ${PROJECT_NAME})
 file(MAKE_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/logs")
+
+enable_testing()
+add_test(NAME ${PROJECT_NAME} COMMAND ${PROJECT_NAME})