cmake: Allow Catch test discovery

Allows individual unit-tests to be discovered, tested, and debugged by IDEs without having to run _all_ of the unit-tests just to debug one specific test.

externals/CMakeLists.txt

@@ -60,6 +60,7 @@ if (ENABLE_TESTS)
         add_subdirectory(catch2)
     endif()
     target_link_libraries(catch2 INTERFACE Catch2::Catch2WithMain)
+	include(Catch)
 endif()
 
 # Crypto++

src/tests/CMakeLists.txt

@@ -31,6 +31,7 @@ if (ENABLE_LIBRETRO)
 endif()
 
 add_test(NAME tests COMMAND tests)
+catch_discover_tests(tests)
 
 if (CITRA_USE_PRECOMPILED_HEADERS)
     target_precompile_headers(tests PRIVATE precompiled_headers.h)