Cannot build 5.20.5 using GCC15

[vincent-noel]

In file included from D:/a/_temp/msys64/tmp/libsbml-5.20.5/src/sbml/html2md/html2md.cpp:4:
D:/a/_temp/msys64/tmp/libsbml-5.20.5/src/sbml/html2md/html2md.h:322:3: error: 'uint8_t' does not name a type
  322 |   uint8_t index_ol = 0;
      |   ^~~~~~~
D:/a/_temp/msys64/tmp/libsbml-5.20.5/src/sbml/html2md/html2md.h:10:1: note: 'uint8_t' is defined in header '<cstdint>'; this is probably fixable by adding '#include <cstdint>'
    9 | #include <unordered_map>
  +++ |+#include <cstdint>
   10 | 

I noticed this building on MSYS2, which always uses latest GCC, and I was able to reproduce it on ubuntu 25.04.