Boost.Python can not find python on windows if path contains spaces

This issue was mentioned [here](https://github.com/microsoft/vcpkg/issues/5732), when building boost.python with numpy.
Everything is ok if python is installed in path without spaces, and it does not find system python (and thereafter numpy) if spaces are present in the path. So attached [file](https://github.com/boostorg/build/files/6778610/FixSpacesInPathIssue.patch.txt) can be applied as patch (mb it is not the best fix, but still works, please have a look).

I faced this issue on boost version 1.75.0

Review the linked FixSpacesInPathIssue.patch.txt and the related vcpkg issue for context, then locate the Boost.Python discovery path in the build configuration. Reproduce the failure with Python installed under a path containing spaces and verify that system Python and NumPy are found afterward, including on Boost 1.75.0.

Written by the indexing model from the issue text.