Dropping lower constraints testing (stable Xena)

This topic was discussed on the ML and QA team proposed to
to test lower-constraints [1].

As decided in Neutron meeting, stable branches will drop this
CI job [2].

To pass gates, this also excludes consider-using-f-string from pylint
pep8 tests to avoid PEP8 failures with recent setuptools [3]

[1]http://lists.openstack.org/pipermail/openstack-discuss/2020-December/019390.html
[2]http://eavesdrop.openstack.org/meetings/networking/2021/networking.2021-01-12-14.00.log.html
[3]http://lists.openstack.org/pipermail/openstack-discuss/2021-September/024987.html

Change-Id: Ife8e2823f8ab43702f08eae6853efa3f86e3d43b

.pylintrc

@@ -56,6 +56,7 @@ disable=
  bad-continuation,
  consider-iterating-dictionary,
  consider-using-enumerate,
+ consider-using-f-string,
  invalid-name,
  len-as-condition,
  misplaced-comparison-constant,

.zuul.yaml

@@ -3,7 +3,6 @@
       - check-requirements
       - publish-openstack-docs-pti
       - openstack-cover-jobs
-      - openstack-lower-constraints-jobs
       - openstack-python3-xena-jobs
       - lib-forward-testing-python3
       - release-notes-jobs-python3

lower-constraints.txt

@@ -1,101 +0,0 @@
-alabaster==0.7.10
-alembic==0.9.6
-amqp==2.5.0
-appdirs==1.4.3
-astroid==2.1.0
-Babel==2.3.4
-bandit==1.1.0
-cachetools==2.0.0
-contextlib2==0.4.0
-coverage==4.0
-ddt==1.0.1
-debtcollector==1.19.0
-decorator==4.0.0
-docutils==0.11
-dulwich==0.15.0
-eventlet==0.18.2
-extras==1.0.0
-fasteners==0.7.0
-fixtures==3.0.0
-flake8==3.6.0
-future==0.16.0
-futurist==1.2.0
-gitdb==0.6.4
-GitPython==1.0.1
-greenlet==0.4.15
-imagesize==0.7.1
-iso8601==0.1.11
-isort==4.3.21
-Jinja2==2.10
-keystoneauth1==3.14.0
-kombu==4.6.1
-linecache2==1.0.0
-Mako==0.4.0
-MarkupSafe==1.1.1
-monotonic==0.6
-mox3==0.20.0
-msgpack-python==0.4.0
-netaddr==0.7.18
-netifaces==0.10.4
-os-api-ref==1.4.0
-os-client-config==1.28.0
-os-ken==0.3.0
-os-traits==0.9.0
-oslo.concurrency==3.26.0
-oslo.config==8.0.0
-oslo.context==2.22.0
-oslo.db==4.44.0
-oslo.i18n==3.20.0
-oslo.log==4.3.0
-oslo.messaging==7.0.0
-oslo.middleware==3.31.0
-oslo.policy==3.6.2
-oslo.serialization==2.25.0
-oslo.service==1.24.0
-oslo.utils==4.5.0
-oslo.versionedobjects===1.31.2
-oslotest==3.2.0
-osprofiler===1.4.0
-Paste==2.0.2
-PasteDeploy==1.5.0
-pbr==4.0.0
-pecan===1.0.0
-pika==0.10.0
-pika-pool==0.1.3
-prettytable==0.7.2
-Pygments==2.2.0
-pyinotify==0.9.6
-pylint==2.2.0
-pyparsing==2.1.0
-python-dateutil==2.7.0
-python-editor==1.0.3
-python-mimeparse==1.6.0
-python-subunit==1.0.0
-pytz==2013.6
-PyYAML==5.3.1
-reno==3.1.0
-repoze.lru==0.7
-requests==2.18.0
-requestsexceptions==1.2.0
-rfc3986==1.2.0
-Routes==2.3.1
-setproctitle==1.1.10
-snowballstemmer==1.2.1
-SQLAlchemy==1.2.0
-sqlalchemy-migrate==0.11.0
-sqlparse==0.2.2
-statsd==3.2.1
-stestr==1.0.0
-stevedore==1.20.0
-Tempita==0.5.2
-tenacity==6.0.0
-testrepository==0.0.18
-testresources==2.0.0
-testscenarios==0.4
-testtools==2.2.0
-traceback2==1.4.0
-unittest2==1.1.0
-vine==1.1.4
-weakrefmethod==1.0.2
-WebOb==1.7.1
-wrapt==1.7.0

tox.ini

@@ -127,9 +127,3 @@ commands = bandit -r neutron_lib -x tests -n5 -s B104,B303,B311
 
 [hacking]
 import_exceptions = neutron_lib._i18n
-
-[testenv:lower-constraints]
-deps =
-  -c{toxinidir}/lower-constraints.txt
-  -r{toxinidir}/test-requirements.txt
-  -r{toxinidir}/requirements.txt