run-tests: cleanup windows generation of the python / python3 pointeur
They are no need to generate then in RUNTESTDIR and we don't need a python2
executable. (because not test ever use `python2` explicitly).
This is probably still not perfect, but at least it is better.
Differential Revision: https://phab.mercurial-scm.org/D11045
#require docutils gettext
$ $TESTDIR/check-gendoc de
checking for parse errors
Die Dateien werden dem Projektarchiv beim n\xc3\xa4chsten \xc3\x9cbernehmen (commit) hinzugef\xc3\xbcgt. Um dies vorher r\xc3\xbcckg\xc3\xa4ngig zu machen, siehe:hg:`forget`. (esc)
warning: please have a space before :hg: