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: I3d7ad8a49bbb63fd00ae9523243135a24419c465

lower-constraints.txt

@@ -1,25 +0,0 @@
-PyYAML==3.13
-appdirs==1.3.0
-cliff==2.8.0
-coverage==4.0
-ddt==1.0.1
-dogpile.cache==0.8.0
-fixtures==3.0.0
-jsonschema==3.2.0
-keystoneauth1==3.11.0
-openstacksdk==0.18.0
-osc-lib==2.0.0
-oslo.config==6.3.0
-oslo.log==3.36.0
-oslo.utils==3.33.0
-oslotest==3.2.0
-pbr==2.0.0
-python-cinderclient==7.2.1
-python-novaclient==9.0.0
-python-openstackclient==3.12.0
-requests-mock==1.2.0
-requests==2.14.2
-stestr==1.0.0
-stevedore==1.20.0
-tempest==25.0.0
-testtools==2.2.0

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

@@ -91,9 +91,3 @@ application-import-names = ironicclient
 
 [hacking]
 import_exceptions = testtools.matchers, ironicclient.common.i18n
-
-[testenv:lower-constraints]
-deps =
-  -c{toxinidir}/lower-constraints.txt
-  -r{toxinidir}/test-requirements.txt
-  -r{toxinidir}/requirements.txt

zuul.d/project.yaml

@@ -2,7 +2,6 @@
     templates:
       - check-requirements
       - openstack-cover-jobs
-      - openstack-lower-constraints-master-branch-jobs
       - openstack-python3-zed-jobs
       - openstackclient-plugin-jobs
       - publish-openstack-docs-pti