bpo-43327: Fix the docs for PyImport_ImportFrozenModuleObject() (GH-24659)

The docs stated that PyImport_ImportFrozenModuleObject() returns a
new reference, but it actually returns an int.

(cherry picked from commit 62a5dc13e941d01beb215db4218a10977914ab55)

Co-authored-by: Zackery Spytz <zspytz@gmail.com>
Co-authored-by: Kumar Aditya <59607654+kumaraditya303@users.noreply.github.com>