There's a merged pull request on the void-packages repository

common/chroot-style: clean up bwrap.sh.
https://github.com/void-linux/void-packages/pull/34023

Description:
--dev-bind isn't necessary in any case it was being used for. We can
also use --ro-bind for /void-packages.

A possible future improvement would be to mount / read only during the
actual build.

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