tests: add proper catch2 handling

Add proper catch2 support:
 - add catch2 as a submodule
 - add cmake function to add test easily
 - discover each test in test binary
 - remove copies of catch.hpp
 - do not try to process tests for rt1051

Do not test internals of utf8, only public interface (nasty bugs could
occur otherwise).

Signed-off-by: Marcin Smoczyński <smoczynski.marcin@gmail.com>

module-db/tests/SMSRecord_tests.cpp

@@ -1,4 +1,4 @@
-#include "catch.hpp"
+#include <catch2/catch.hpp>
 
 #include <Database/Database.hpp>
 #include <Databases/ContactsDB.hpp>
@@ -194,4 +194,4 @@ TEST_CASE("SMS Record tests")
     REQUIRE(smsRecInterface.GetCount() == 0);
 
     Database::Deinitialize();
-}
+}