[BUG]: writes to std::array is not working

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What version (or hash if on master) of pybind11 are you using?

v3.0

Problem description

if an array is used in a struct as a member variable, writes from python are not registered

Reproducible example code

#include <array>
#include <pybind11/pybind11.h>

namespace py = pybind11;

struct foo {
  foo() = default;
  std::array<uint32_t, 2> bar;
};

PYBIND11_MODULE(my_module, m) {
  py::class_<foo>(m, "foo")
      .def(py::init<>())
      .def_readwrite("bar", &foo::bar);
}

import my_module

foo = my_module.foo()
foo.bar[0] = 5
print(foo.bar[0])

Is this a regression? Put the last known working version here if it is.

No response

Start with the provided C++ binding using std::array and the Python assignment example, then trace the def_readwrite path for array members. Reproduce the reported behavior and verify the fix by confirming that assigning foo.bar[0] from Python is reflected when it is read back.