This is part XXVII of cmd engine rewrite.
It covers:
- fixing a regression introduced when looping up
for program names with several dots in their names
(eg. foo.bat can invoke foo.bat.cmd)
- fix an incorrect handling of 'SET =' command
- a couple of cleanups in SET command
--
https://gitlab.winehq.org/wine/wine/-/merge_requests/6615