Drop lower-constraints.txt and its testing

As discussed in TC PTG[1] and TC resolution[2], we are
dropping the lower-constraints.txt file and its testing.
We will keep lower bounds in the requirements.txt file but
with a note that these are not tested lower bounds and we
try our best to keep them updated.

[1] https://etherpad.opendev.org/p/tc-zed-ptg#L326
[2] https://governance.openstack.org/tc/resolutions/20220414-drop-lower-constraints.html#proposal

Change-Id: I24fd4700d59b30e4e5b3fed6c892a4f8ade7bb47

.zuul.yaml

@@ -2,7 +2,6 @@
     templates:
       - check-requirements
       - openstack-cover-jobs
-      - openstack-lower-constraints-jobs
       - openstack-python3-zed-jobs
       - publish-openstack-docs-pti
       - release-notes-jobs-python3

lower-constraints.txt

@@ -1,116 +0,0 @@
-alabaster==0.7.10
-alembic==0.9.6
-amqp==2.2.2
-appdirs==1.4.3
-astroid==1.3.8
-beautifulsoup4==4.6.0
-cachetools==2.0.1
-certifi==2018.1.18
-chardet==3.0.4
-click==6.7
-contextlib2==0.5.5
-coverage==4.0
-ddt==1.0.1
-debtcollector==1.19.0
-decorator==4.2.1
-docutils==0.14
-dogpile.cache==0.6.5
-dulwich==0.19.0
-enum-compat==0.0.2
-eventlet==0.18.2
-extras==1.0.0
-fasteners==0.14.1
-fixtures==3.0.0
-Flask==1.0.2
-futurist==1.6.0
-greenlet==0.4.13
-idna==2.6
-imagesize==1.0.0
-iso8601==0.1.11
-itsdangerous==0.24
-Jinja2==2.10
-keystoneauth1==3.13.0
-keystonemiddleware==4.17.0
-kombu==4.2.0
-linecache2==1.0.0
-logilab-common==1.4.1
-logutils==0.3.5
-Mako==1.0.7
-MarkupSafe==1.1.1
-microversion-parse===0.2.1
-monotonic==1.4
-mox3==0.25.0
-msgpack==0.5.6
-netaddr==0.7.18
-netifaces==0.10.6
-openstackdocstheme==2.2.1
-os-api-ref==1.4.0
-os-client-config==1.29.0
-oslo.cache==1.29.0
-oslo.concurrency==3.26.0
-oslo.config==6.8.0
-oslo.context==2.22.0
-oslo.db==4.40.0
-oslo.i18n==3.15.3
-oslo.log==3.36.0
-oslo.messaging==5.29.0
-oslo.middleware==3.31.0
-oslo.policy==3.6.0
-oslo.serialization==2.18.0
-oslo.service==1.34.0
-oslo.upgradecheck==1.3.0
-oslo.utils==4.5.0
-oslotest==3.2.0
-Paste==2.0.3
-PasteDeploy==1.5.2
-pbr==2.0.0
-pecan==1.0.0
-pika-pool==0.1.3
-pika==0.10.0
-prettytable==0.7.2
-pycadf==2.7.0
-Pygments==2.2.0
-pyinotify==0.9.6
-pylint==1.9.1
-pyparsing==2.2.0
-python-dateutil==2.7.0
-python-editor==1.0.3
-python-keystoneclient==3.8.0
-python-mimeparse==1.6.0
-python-neutronclient==6.0.0
-python-novaclient==9.1.0
-python-subunit==1.2.0
-pytz==2018.3
-PyYAML==5.1
-reno==3.1.0
-repoze.lru==0.7
-requests==2.18.4
-requestsexceptions==1.4.0
-retrying==1.3.3
-rfc3986==1.2.0
-Routes==2.3.1
-simplegeneric==0.8.1
-simplejson==3.13.2
-snowballstemmer==1.2.1
-Sphinx==2.0.0
-sphinxcontrib-websupport==1.0.1
-SQLAlchemy==1.0.10
-sqlparse==0.2.4
-statsd==3.2.2
-stevedore==1.20.0
-Tempita==0.5.2
-tenacity==4.9.0
-stestr==2.0.0
-testresources==2.0.1
-testscenarios==0.4
-testtools==2.2.0
-traceback2==1.4.0
-unittest2==1.1.0
-urllib3==1.22
-vine==1.1.4
-waitress==1.1.0
-WebOb==1.7.1
-WebTest==2.0.29
-Werkzeug==0.14.1
-wrapt==1.10.11
-WSME==0.8.0

requirements.txt

@@ -1,3 +1,7 @@
+# Requirements lower bounds listed here are our best effort to keep them up to
+# date but we do not test them so no guarantee of having them all correct. If
+# you find any incorrect lower bounds, let us know or propose a fix.
+
 # The order of packages is significant, because pip processes them in the order
 # of appearance. Changing the order has an impact on the overall integration
 # process, which may cause wedges in the gate later.

tox.ini

@@ -102,12 +102,6 @@ commands =
 commands =
     oslopolicy-sample-generator --config-file etc/blazar/blazar-policy-generator.conf
 
-[testenv:lower-constraints]
-deps =
-  -c{toxinidir}/lower-constraints.txt
-  -r{toxinidir}/requirements.txt
-  -r{toxinidir}/test-requirements.txt
-
 # This environment can be used to quickly validate that all needed system
 # packages required to successfully execute test targets are installed
 [testenv:bindep]