Comment 20 for bug 1959971

(And ZFS setup in Ubiquity was also updated to match:

https://git.launchpad.net/ubiquity/commit/scripts/zsys-setup?id=36b3970bfb903fa67186b09863c50ac55aaecc44

  zsys-setup: increase minimum bpool partition size to 1792
  This matches zfs bpool size to /boot size as produced by partman-auto.

https://git.launchpad.net/ubiquity/commit/?id=21ebbdf8c087da9e01394d80a3924c2d4f161753
  zsys: fix comment

  bpool minimum size was previously increased to 1.75G. Update comment to match.
)