lbzip2: 2.2 (new formula).

A parallel bzip2 compatible (un)archiver.

Closes #17767.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>
lbzip2: add test.
rbenv: use HOMEBREW_PREFIX.

Closes #17778.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>