Instead we use $(PYTHON_FOR_REGEN) .../deepfreeze.py with the
frozen .h file as input, as we did for Windows in bpo-45850.
We also get rid of the code that generates the .h files
when make regen-frozen is run (i.e., .../make_frozen.py),
and the MANIFEST file.
Restore Python 3.8 and 3.9 as Windows host Python again
Co-authored-by: Kumar Aditya <59607654+kumaraditya303@users.noreply.github.com>
Implement changes to build with deep-frozen modules on Windows.
Note that we now require Python 3.10 as the "bootstrap" or "host" Python.
This causes a modest startup speed (around 7%) on Windows.
Fix logic for retrying nuget.exe download with Python.
Add support for HOST_PYTHON variable.
Clear internal environment variables used in find_python.bat
Use HOST_PYTHON as the actual Python if it is recent enough.
Adds HOST_PYTHON variable to AppVeyor configuration
