Update build.yml to add MSYS2 ucrt64, clang32 and clang64 build

[mcuee]

This PR adds github action build for MSYS2 ucrt64, clang32 and clang64 for Windows.
clangarm64 is not added as it is still not as mature.

Reference:
https://www.msys2.org/docs/environments/

[mcuee]

clang compilers sometimes capture more codes issues compared to gcc and MSVC.

For example, the following warnings are generated by clang64 build against git main.
https://github.com/avrdudes/avrdude/actions/runs/7442516451/job/20246066588

[ 61%] Building C object src/CMakeFiles/libavrdude.dir/ser_win32.c.obj
D:/a/avrdude/avrdude/src/ser_win32.c:440:3: warning: comparison of integers of different signs: 'SOCKET' (aka 'unsigned long long') and 'const int' [-Wsign-compare]
  440 |                 FD_SET(fd->ifd, &rfds);
      |                 ^~~~~~~~~~~~~~~~~~~~~~
D:/a/_temp/msys64/clang64/include/psdk_inc/_fd_types.h:77:40: note: expanded from macro 'FD_SET'
   77 |                 if (((fd_set *)(set))->fd_array[__i] == (fd)) {         \
      |                     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^   ~~
D:/a/avrdude/avrdude/src/ser_win32.c:[56](https://github.com/avrdudes/avrdude/actions/runs/7442516451/job/20246066588#step:5:57)1:3: warning: comparison of integers of different signs: 'SOCKET' (aka 'unsigned long long') and 'const int' [-Wsign-compare]
  5[61](https://github.com/avrdudes/avrdude/actions/runs/7442516451/job/20246066588#step:5:62) |                 FD_SET(fd->ifd, &rfds);
      |                 ^~~~~~~~~~~~~~~~~~~~~~
D:/a/_temp/msys[64](https://github.com/avrdudes/avrdude/actions/runs/7442516451/job/20246066588#step:5:65)/clang64/include/psdk_inc/_fd_types.h:77:40: note: expanded from macro 'FD_SET'
   77 |                 if (((fd_set *)(set))->fd_array[__i] == (fd)) {         \
      |                     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^   ~~
2 warnings generated.

[stefanrueger]

@mcuee I don't think these two warnings are significant, and I suggest not fixing these as that's not critical for v7.3

[mcuee]

@mcuee I don't think these two warnings are significant, and I suggest not fixing these as that's not critical for v7.3

I agree.