Michael Herrmann 5096a546df Fix errors in macOS .pkg postinstall script (#36483) ...

Eg. when installing from Brave-Browser-universal.pkg, the previous
implementation gave the following `postinstall` errors in
`/var/log/install.log`:

chmod: /Applications/Brave Browser universal.app: No such file or directory
chown: /Applications/Brave Browser universal.app: No such file or directory
chgrp: /Applications/Brave Browser universal.app: No such file or directory

2026-05-15 19:43:26 +01:00

..

postinstall

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preinstall

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