test-patchbomb: fix the test
With the experimental config `progress.estimate` removed, the progress
output in `test-patchbomb.t` has a minor change: it shows ETA since the
beginning.
(This could be folded into f428c3)
FROM centos:centos6
RUN yum install -y gcc
RUN yum install -y python-devel python-docutils
RUN yum install -y make
RUN yum install -y rpm-build
RUN yum install -y gettext
RUN yum install -y tar
# For creating repo meta data
RUN yum install -y createrepo
# For python
RUN yum install -y readline-devel openssl-devel ncurses-devel zlib-devel bzip2-devel