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: Id276f7efef3ef955b4c0b4b8d62f7c38cb535b33

lower-constraints.txt

@@ -1,68 +0,0 @@
-amqp==5.0.0
-Babel==2.3.4
-bashate==0.5.1
-bcrypt==3.1.3
-coverage==4.0
-cryptography==2.7
-docutils==0.14
-dogpile.cache==1.0.2
-fixtures==3.0.0
-flake8-docstrings==0.2.1.post1
-flake8==2.6.0
-Flask===1.0.2
-Flask-RESTful===0.3.5
-freezegun==0.3.6
-hacking==1.1.0
-iso8601==0.1.12
-jsonschema==3.2.0
-keystoneauth1==3.4.0
-keystonemiddleware==7.0.0
-ldappool===2.3.1
-lxml==4.5.0
-mock==2.0.0
-msgpack==0.5.0
-oauthlib==0.6.2
-os-api-ref==1.4.0
-oslo.cache==1.26.0
-oslo.concurrency==3.26.0
-oslo.config==6.8.0
-oslo.context==2.22.0
-oslo.db==6.0.0
-oslo.i18n==3.15.3
-oslo.log==3.44.0
-oslo.messaging==5.29.0
-oslo.middleware==3.31.0
-oslo.policy==3.10.0
-oslo.serialization==2.18.0
-oslo.upgradecheck==1.3.0
-oslo.utils==3.33.0
-oslotest==3.2.0
-osprofiler==1.4.0
-passlib==1.7.0
-pbr==2.0.0
-pep257==0.7.0
-pika==0.10.0
-pycadf==1.1.0
-pycodestyle==2.0.0
-python-ldap===3.0.0
-pymongo===3.0.2
-pysaml2==5.0.0
-PyJWT==1.6.1
-PyMySQL==0.8.0
-python-keystoneclient==3.8.0
-python-memcached===1.56
-pytz==2013.6
-requests==2.14.2
-scrypt==0.8.0
-six==1.10.0
-sqlalchemy-migrate==0.13.0
-SQLAlchemy==1.3.0
-stestr==1.0.0
-stevedore==1.20.0
-tempest==17.1.0
-testtools==2.2.0
-urllib3==1.22
-vine==1.3.0
-WebOb==1.7.1
-WebTest==2.0.27
-Werkzeug==0.14.1

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

@@ -188,12 +188,6 @@ paths = ./keystone/tests/hacking
 deps = bindep
 commands = bindep test
 
-[testenv:lower-constraints]
-deps =
-  -c{toxinidir}/lower-constraints.txt
-  -r{toxinidir}/test-requirements.txt
-  .[ldap,memcache,mongodb]
-
 [testenv:protection]
 commands =
   find keystone -type f -name "*.pyc" -delete