Generate `Modules/getbuildinfo.h` when building Python to get build information statically

Hi, In short, please test my PR gh-158951 if you cross-compile Python or build Python in a specific way. The PR changes Python build system to run a new generate_getbuildinfo.py script which generates getbuildinfo.h file. Recently, I modified Python to no longer use a static buffer of 300 bytes, but allocate memory on the heap to create sys.version string in Py_GetVersion(). Previously, the compiler and build information (Git branch/tag/verison, date and time) could be truncated in sys.versio...