ArduinoJson 6.15.2 * CMake: don't build tests when imported in another project * CMake: made project arch-independent * Visual Studio: fixed error C2766 with flag `/Zc:__cplusplus` (issue #1250) * Added support for `JsonDocument` to `copyArray()` (issue #1255) * Added support for `enum`s in `as<T>()` and `is<T>()` (issue #1256) * Added `JsonVariant` as an input type for `deserializeXxx()`