Remove lower-constraints job

As discussed during the upstream ironic community meeting on
Monday Dec 14 2020, the lower-constraints job is being removed.

Change-Id: Iab279c57676dba8faa87ab7523e577d3b65eb428

lower-constraints.txt

@@ -1,63 +0,0 @@
-appdirs==1.3.0
-Babel==2.3.4
-bcrypt==3.1.3
-cffi==1.1.0
-chardet==3.0.4
-coverage==4.0
-debtcollector==1.2.0
-doc8==0.6.0
-docutils==0.11
-eventlet==0.18.2
-extras==1.0.0
-fasteners==0.7.0
-fixtures==3.0.0
-future==0.16.0
-greenlet==0.4.10
-ifaddr==0.1.6
-iso8601==0.1.11
-keystoneauth1==3.4.0
-linecache2==1.0.0
-monotonic==0.6
-mox3==0.20.0
-msgpack-python==0.4.0
-netaddr==0.7.18
-netifaces==0.10.4
-os-client-config==1.28.0
-oslo.concurrency==3.26.0
-oslo.config==5.2.0
-oslo.context==2.19.2
-oslo.i18n==3.15.3
-oslo.log==3.36.0
-oslo.serialization==2.18.0
-oslo.service==1.24.0
-oslo.utils==3.33.0
-oslotest==3.2.0
-Paste==2.0.2
-PasteDeploy==1.5.0
-pbr==2.0.0
-pycodestyle==2.3.1
-Pygments==2.2.0
-pyinotify==0.9.6
-pyparsing==2.1.0
-python-dateutil==2.5.3
-python-mimeparse==1.6.0
-python-subunit==1.0.0
-pytz==2013.6
-PyYAML==3.12
-repoze.lru==0.7
-requests==2.14.2
-requestsexceptions==1.2.0
-restructuredtext-lint==1.1.1
-rfc3986==0.3.1
-Routes==2.3.1
-six==1.14.0
-stestr==1.0.0
-stevedore==1.20.0
-tenacity==6.2.0
-testrepository==0.0.20
-testtools==2.2.0
-traceback2==1.4.0
-unittest2==1.1.0
-WebOb==1.7.1
-wrapt==1.7.0
-zeroconf==0.24.0

zuul.d/project.yaml

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