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.

Note that we make the Python 3.6 non-voting because it is failing due to
Nova dropping support for it.

[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: If34a9d89d8b5779b6eb4f35b171e64c5f6c1902e

.zuul.yaml

@@ -1,6 +1,13 @@
 - project:
     templates:
       - check-requirements
-      - openstack-lower-constraints-jobs
       - openstack-python3-yoga-jobs
       - release-notes-jobs-python3
+    check:
+      jobs:
+        - openstack-tox-py36:
+            voting: false
+    gate:
+      jobs:
+        - openstack-tox-py36:
+            voting: false

lower-constraints.txt

@@ -1,166 +0,0 @@
-alembic==1.5.0
-amqp==2.5.0
-appdirs==1.4.3
-asn1crypto==0.24.0
-attrs==17.4.0
-automaton==1.14.0
-bandit==1.1.0
-cachetools==2.0.1
-castellan==0.16.0
-cffi==1.14.0
-cliff==2.11.0
-cmd2==0.8.1
-colorama==0.3.9
-coverage==4.0
-cryptography==2.7
-cursive==0.2.1
-dataclasses==0.7
-ddt==1.2.1
-debtcollector==1.19.0
-decorator==4.1.0
-deprecation==2.0
-dogpile.cache==0.6.5
-enum-compat==0.0.2
-eventlet==0.30.1
-extras==1.0.0
-fasteners==0.14.1
-fixtures==3.0.0
-future==0.16.0
-futurist==1.8.0
-gabbi==1.35.0
-gitdb2==2.0.3
-GitPython==2.1.8
-greenlet==0.4.15
-idna==2.6
-iso8601==0.1.11
-Jinja2==2.10
-jmespath==0.9.3
-jsonpatch==1.21
-jsonpath-rw==1.4.0
-jsonpath-rw-ext==1.1.3
-jsonpointer==2.0
-jsonschema==3.2.0
-keystoneauth1==3.16.0
-keystonemiddleware==4.20.0
-kombu==4.6.1
-linecache2==1.0.0
-lxml==4.5.0
-Mako==1.0.7
-MarkupSafe==1.1.1
-microversion-parse==0.2.1
-mock==3.0.0
-msgpack==0.6.0
-msgpack-python==0.5.6
-munch==2.2.0
-mypy==0.761
-netaddr==0.7.18
-netifaces==0.10.4
-networkx==2.1.0
-numpy==1.19.0
-openstacksdk==0.35.0
-os-brick==5.2
-os-client-config==1.29.0
-os-resource-classes==1.1.0
-os-service-types==1.7.0
-os-traits==2.7.0
-os-vif==1.15.2
-os-win==5.5.0
-osc-lib==1.10.0
-oslo.cache==1.26.0
-oslo.concurrency==4.5.0
-oslo.config==8.6.0
-oslo.context==3.4.0
-oslo.db==10.0.0
-oslo.i18n==5.1.0
-oslo.log==4.6.1
-oslo.limit==1.5.0
-oslo.messaging==10.3.0
-oslo.middleware==3.31.0
-oslo.policy==3.7.0
-oslo.privsep==2.6.2
-oslo.reports==1.18.0
-oslo.rootwrap==5.8.0
-oslo.serialization==4.2.0
-oslo.service==2.8.0
-oslo.upgradecheck==1.3.0
-oslo.utils==4.12.1
-oslo.versionedobjects==1.35.0
-oslo.vmware==3.6.0
-oslotest==3.8.0
-osprofiler==1.4.0
-ovs==2.10.0
-ovsdbapp==0.15.0
-packaging==20.4
-paramiko==2.7.1
-Paste==2.0.2
-PasteDeploy==1.5.0
-pbr==5.8.0
-pluggy==0.6.0
-ply==3.11
-prettytable==0.7.1
-psutil==3.2.2
-psycopg2-binary==2.8
-py==1.5.2
-pyasn1==0.4.2
-pyasn1-modules==0.2.1
-pycadf==2.7.0
-pycparser==2.18
-pyinotify==0.9.6
-pyroute2==0.5.4
-PyJWT==1.7.0
-PyMySQL==0.8.0
-pyOpenSSL==17.5.0
-pyparsing==2.2.0
-pyperclip==1.6.0
-pypowervm==1.1.15
-pytest==3.4.2
-python-barbicanclient==4.5.2
-python-cinderclient==3.3.0
-python-dateutil==2.7.0
-python-editor==1.0.3
-python-glanceclient==2.8.0
-python-ironicclient==3.0.0
-python-keystoneclient==3.15.0
-python-mimeparse==1.6.0
-python-neutronclient==7.1.0
-python-subunit==1.4.0
-pytz==2018.3
-PyYAML==5.1
-repoze.lru==0.7
-requests==2.25.1
-requests-mock==1.2.0
-requestsexceptions==1.4.0
-retrying==1.3.3
-rfc3986==1.2.0
-Routes==2.3.1
-simplejson==3.13.2
-six==1.15.0
-smmap2==2.0.3
-sortedcontainers==2.1.0
-SQLAlchemy==1.4.13
-sqlalchemy-migrate==0.13.0
-sqlparse==0.2.4
-statsd==3.2.2
-stestr==2.0.0
-stevedore==1.20.0
-suds-jurko==0.6
-taskflow==3.8.0
-Tempita==0.5.2
-tenacity==6.3.1
-testrepository==0.0.20
-testresources==2.0.0
-testscenarios==0.4
-testtools==2.5.0
-tooz==1.58.0
-traceback2==1.4.0
-types-paramiko==0.1.3
-unittest2==1.1.0
-urllib3==1.22
-vine==1.1.4
-voluptuous==0.11.1
-warlock==1.3.1
-WebOb==1.8.2
-websockify==0.9.0
-wrapt==1.10.11
-wsgi-intercept==1.7.0
-zVMCloudConnector==1.3.0

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

@@ -39,12 +39,6 @@ show-source = true
 builtins = _
 exclude = .venv,.git,.tmp,.tox,dist,doc,*lib/python*,*egg,tools
 
-[testenv:lower-constraints]
-install_command = {toxinidir}/tools/tox_install.sh {toxinidir}/lower-constraints.txt {opts} {packages}
-deps =
-  -r{toxinidir}/requirements.txt
-  -r{toxinidir}/test-requirements.txt
-
 [testenv:releasenotes]
 deps = -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
        -r{toxinidir}/doc/requirements.txt