Use `--dev` option of bubblewrap

Description

The --dev option of bubblewrap provides a more complete set of /dev entries without exposing host devices.

This adds the device node /dev/tty and the symlinks /dev/stdin, /dev/stdout, /dev/stderr, /dev/fd, /dev/core and /dev/ptmx, and mounts /dev/pts.

Validation

Please note steps the reviewer should take to be able to test this MR; any necessary setup they might need, what results they should be looking for to verify.

Issues addressed

Fixes #7 (closed).

assigned to @juergbi

approved this merge request

approved this merge request

merged

Looks like we now need /dev/ptmx removed from sandbox for freedesktop-sdk after this change https://github.com/fosslinux/live-bootstrap/commit/d0a522113f36f683345e5f0efb6917ad9793618f#diff-bb3655625ec3a00693f39b72442d345b962ebafafe06d36cb6cff6dc6ba4e566L445

mentioned in merge request freedesktop-sdk/freedesktop-sdk-binary-seed!58 (merged)