tests: Switch to using CentOS8 for the Docker tests

This also moves the packages to be installed into a file that can be
shared between test methods.

It drops several packages that are unnecessary for testing, and excludes
those paths from pylint checks using pocketlint.

Related: rhbz#1785154

Dockerfile.test

@@ -1,36 +1,8 @@
-FROM registry.fedoraproject.org/fedora:28
-RUN  dnf -y install \
-  anaconda-tui \
-  libgit2-glib \
-  libselinux-python3 \
-  make \
-  pykickstart \
-  python3-coverage \
-  python3-coveralls \
-  python3-flask \
-  python3-gevent \
-  python3-magic \
-  python3-mako \
-  python3-nose \
-  python3-pocketlint \
-  python3-pylint \
-  python3-pyparted \
-  python3-pytoml \
-  python3-semantic_version \
-  python3-sphinx \
-  python3-rpmfluff \
-  python3-librepo \
-  beakerlib \
-  sudo \
-  tito \
-  rsync \
-  e2fsprogs \
-  xz-lzma-compat \
-  pbzip2 \
-  squashfs-tools \
-  qemu-img \
-  which && \
-  touch /.in-container
+FROM centos:8
+RUN dnf install -y https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm
+COPY ./test-packages .
+RUN dnf -y install $(cat ./test-packages) && touch /.in-container
+RUN pip3 install pocketlint
 RUN useradd weldr
 VOLUME /lorax-ro
 VOLUME /test-results

Makefile

@@ -52,7 +52,7 @@ test:
 					--cover-package=pylorax --cover-inclusive \
 					./tests/pylorax/ ./tests/composer/
 
-	coverage3 report -m
+	coverage-3 report -m
 	[ -f "/usr/bin/coveralls" ] && [ -n "$(COVERALLS_REPO_TOKEN)" ] && coveralls || echo
 
 # need `losetup`, which needs Docker to be in privileged mode (--privileged)

test-packages

@@ -0,0 +1,25 @@
+anaconda-tui
+libgit2-glib
+libselinux-python3
+make
+pykickstart
+python3-coverage
+python3-coveralls
+python3-flask
+python3-gevent
+python3-magic
+python3-mako
+python3-nose
+python3-pylint
+python3-pyparted
+python3-pytoml
+python3-semantic_version
+python3-rpmfluff
+python3-librepo
+sudo
+rsync
+e2fsprogs
+squashfs-tools
+qemu-img
+which
+git

tests/pylint/runpylint.py

@@ -28,7 +28,7 @@ class LoraxLintConfig(PocketLintConfig):
 
     @property
     def ignoreNames(self):
-        return { "bots", "rpmbuild", "tito" }
+        return { "bots", "rpmbuild", "rel-eng", "docs", "test" }
 
     @property
     def extraArgs(self):