.cirrus.yml: add bash to the brew packages

Like the sed we include earlier we want something more recent for
iotests to work.

Fixes: 57ee95ed
Cc: Max Reitz <mreitz@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20200710182238.10675-1-alex.bennee@linaro.org>
1 file changed