Add test to show that relations can be queried with conditions (#1560)

Ignore nested relation mutation when null is given (#1627)

Improve Xdebug in Docker (#1624)

Use DateTime::ATOM for DateTimeTZ ISO 8601 compatibility (#1622)

Test helper `multipartGraphQL` now accepts arrays instead of JSON strings (#1615)

Move phpstan ignores statement to new locations (#1618)