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: Ia3f66b6805704c254295fd663f0260d5d963ed66

.zuul.yaml

@@ -3,6 +3,5 @@
       - check-requirements
       - lib-forward-testing-python3
       - openstack-cover-jobs
-      - openstack-lower-constraints-jobs
       - openstack-python3-wallaby-jobs
       - publish-openstack-docs-pti

lower-constraints.txt

@@ -1,51 +0,0 @@
-alabaster==0.7.10
-appdirs==1.3.0
-Babel==2.3.4
-coverage==4.0
-debtcollector==1.2.0
-docutils==0.11
-dulwich==0.15.0
-extras==1.0.0
-fixtures==3.0.0
-flake8-docstrings==0.2.1.post1
-imagesize==0.7.1
-iso8601==0.1.11
-Jinja2==2.10
-keystoneauth1==3.4.0
-linecache2==1.0.0
-MarkupSafe==1.0
-mccabe==0.2.1
-monotonic==0.6
-mox3==0.20.0
-msgpack-python==0.4.0
-netaddr==0.7.18
-netifaces==0.10.4
-openstackdocstheme==2.2.1
-os-client-config==1.28.0
-oslo.config==5.2.0
-oslo.i18n==3.15.3
-oslo.serialization==2.18.0
-oslo.utils==3.33.0
-oslotest==3.2.0
-pbr==2.0.0
-pep257==0.7.0
-Pygments==2.2.0
-pyparsing==2.1.0
-python-mimeparse==1.6.0
-python-subunit==1.0.0
-pytz==2013.6
-PyYAML==3.12
-requests==2.14.2
-requestsexceptions==1.2.0
-rfc3986==0.3.1
-six==1.10.0
-snowballstemmer==1.2.1
-Sphinx==2.0.0
-sphinxcontrib-apidoc===0.2.0
-sphinxcontrib-websupport==1.0.1
-stevedore==1.20.0
-stestr==2.0.0
-testtools==2.2.0
-traceback2==1.4.0
-unittest2==1.1.0
-wrapt==1.7.0

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

@@ -58,9 +58,3 @@ show-source = True
 # W504 line break after binary operator
 ignore = H405,D100,D101,D102,D103,D104,D105,D200,D202,D203,D204,D205,D208,D400,D401,W503,W504
 exclude = .tox,dist,doc,*.egg,build
-
-[testenv:lower-constraints]
-deps =
-  -c{toxinidir}/lower-constraints.txt
-  -r{toxinidir}/test-requirements.txt
-  -r{toxinidir}/requirements.txt