Clang on Windows: Fix build errors

[franzpoeschel]

Seen this error in multiple PRs:

2025-07-11T14:01:54.3705882Z D:\a\openPMD-api\openPMD-api\src\binding\python\Series.cpp(390,21): error: a template argument list is expected after a name prefixed by the template keyword [-Wmissing-template-arg-list-after-template-kw]
2025-07-11T14:01:54.8783327Z   390 |         >::template call(cl);

    ::auxiliary::ForEachType<
        ::internal::DefineSeriesConstructorPerPathType,
    // First tuple components are eligible types for the path argument
    // second component for the config argument
    // py::object needs to always come last, as a catch-all pattern
#if openPMD_USE_FILESYSTEM_HEADER
        std::tuple<std::string, std::string>,
        std::tuple<std::string, std::filesystem::path>,
        std::tuple<std::string, py::object>,
        std::tuple<std::filesystem::path, std::string>,
        std::tuple<std::filesystem::path, std::filesystem::path>,
        std::tuple<std::filesystem::path, py::object>
#else
        std::tuple<std::string, std::string>,
        std::tuple<std::string, py::object>,
        std::tuple<py::object, std::string>,
        std::tuple<py::object, py::object>
#endif
        >::template call(cl); // line 390, this is a template, but Clang on Windows no longer believes so

First commit is empty to verify that this affects dev already. Second will push a workaround.

This also uncovered a deprecated API call in Pybind.