aur-build: do not export PKGDEST
aur-build: do not export PKGDEST

It appears this can only be done by appending PKGDEST to makepkg.conf.
(Compare the implementation in /bin/makechrootpkg.)

The environment for --build-command is still modified for now, though it
remains disabled by default.

AladW/aurutils,AladW/aurutils