Add #include <cstdint> to compile with gcc13

Add #include <cstdint> to compile with gcc13

From 1233ceec268d5366c66f5e79786ec784042b591b Mon Sep 17 00:00:00 2001
Origin: upstream, https://gitlab.kitware.com/vtk/vtk/-/commit/1233ceec268d5366c66f5e79786ec784042b591b

The `vtkSEPReader` was introduced by MRs !4909 (from my former
collaborator Maxime) and !4938. Then it was highly modified by
!7516. The later MR is the one that introduced the uses of
`std::uint8_t` and `std::uint32_t`.

Those types needs the inclusion of `<cstdint>`.

Gbp-Pq: Name gcc-13.patch