Remove old infra team puppet testing

The OpenDev team is planning on removing Ubuntu Xenial in the nearish
future. One of the things still running on Xenial is our old puppet
testing. We've decided taht we'll just have to manually manage those
nodes going forward without CI as there are few of them at this point
and we really want to clean up old Ubuntus in nodepool and our mirrors.

There is a risk that this will allow things to break without detection
or otherwise create new problems, but this stuff has been neglected so
that risk was there anyway.

Depends-On: https://review.opendev.org/c/openstack/project-config/+/917198
Change-Id: I4560ae9bbb61e950a7baa1d29aaf677403249012

zuul.d/project.yaml

@@ -2,7 +2,6 @@
     templates:
       - system-config-zuul-role-integration
       - system-config-gerrit-images
-      - system-config-puppet-apply-jobs
     check:
       jobs:
         - opendev-tox-docs

zuul.d/puppet.yaml

@@ -1,123 +0,0 @@
-- job:
-    name: system-config-puppet-apply-4-ubuntu-xenial
-    # Required to install z-c for puppet module installs.
-    parent: legacy-base
-    timeout: 1800
-    nodeset: ubuntu-xenial
-    vars:
-      puppet_version: 4
-    required-projects:
-      - opendev/system-config
-      - opendev/ansible-role-puppet
-      - opendev/puppet-bup
-      - opendev/puppet-httpd
-      - opendev/puppet-jeepyb
-      - opendev/puppet-logrotate
-      - opendev/puppet-mysql_backup
-      - opendev/puppet-openstack_infra_spec_helper
-      - opendev/puppet-pip
-      - opendev/puppet-project_config
-      - opendev/puppet-redis
-      - opendev/puppet-simpleproxy
-      - opendev/puppet-ssh
-      - opendev/puppet-storyboard
-      - opendev/puppet-tmpreaper
-      - opendev/puppet-ulimit
-      - opendev/puppet-user
-      - opendev/puppet-vcsrepo
-      - opendev/puppet-zanata
-    pre-run: playbooks/zuul/infra-puppet-apply/pre.yaml
-    run: playbooks/zuul/infra-puppet-apply/run.yaml
-    post-run: playbooks/zuul/infra-puppet-apply/post.yaml
-    files:
-      - Gemfile
-      - Rakefile
-      - modules.env
-      - install_modules.sh
-      - manifests/.*
-      - modules/.*
-      - roles/puppet-install/.*
-      - hiera/.*
-      - inventory/.*
-      - playbooks/install_puppet.yaml
-      - playbooks/remote_puppet_adhoc.yaml
-      - playbooks/remote_puppet_else.yaml
-      - playbooks/service-eavesdrop.yaml
-      - playbooks/update_puppet_version.yaml
-      - playbooks/roles/disable-puppet-agent/.*
-      - playbooks/roles/puppet-run/.*
-      - playbooks/roles/puppet-setup-ansible/.*
-      - playbooks/zuul/infra-puppet-apply/.*
-      - playbooks/zuul/templates/.*
-
-- job:
-    name: system-config-puppet-beaker-rspec-infra
-    parent: legacy-base
-    description: |
-      Base job for beaker-rspec tests for Infra's puppet modules.
-    nodeset: ubuntu-xenial
-    pre-run: playbooks/zuul/infra-puppet-beaker-rspec/pre.yaml
-    run: playbooks/zuul/infra-puppet-beaker-rspec/run.yaml
-    vars:
-      nodeset: nodepool-xenial
-      project_src_dir: "{{ zuul.project.src_dir }}"
-    timeout: 3600
-    irrelevant-files:
-      - ^.*\.md$
-      - ^.*\.rst$
-      - ^doc/.*$
-      - ^etc/.*$
-      - ^metadata.json$
-      - ^releasenotes/.*$
-      - ^test-requirements.txt$
-    required-projects:
-      - openstack/project-config
-      - opendev/system-config
-      - opendev/puppet-openstack_infra_spec_helper
-      - opendev/puppet-mysql_backup
-      - opendev/puppet-pip
-      - opendev/puppet-project_config
-      - opendev/puppet-httpd
-      - opendev/puppet-redis
-      - opendev/puppet-zanata
-      - opendev/puppet-tmpreaper
-      - opendev/puppet-ulimit
-      - opendev/puppet-logrotate
-      - opendev/puppet-storyboard
-      - opendev/puppet-simpleproxy
-      - opendev/puppet-bup
-      - opendev/puppet-ssh
-      - opendev/puppet-user
-      - opendev/puppet-jeepyb
-      - opendev/puppet-vcsrepo
-
-- job:
-    name: system-config-puppet-beaker-rspec-puppet-4-infra
-    parent: system-config-puppet-beaker-rspec-infra
-    description: |
-      Run beaker-rspec functional tests with puppet 4 on Ubuntu Xenial.
-    vars:
-      puppet_version: 4
-
-- project-template:
-    name: system-config-puppet-apply-jobs
-    description: |
-      Runs puppet apply tests for OpenStack Infrastructure.
-    check:
-      jobs:
-        - system-config-puppet-apply-4-ubuntu-xenial
-    gate:
-      jobs:
-        - system-config-puppet-apply-4-ubuntu-xenial
-
-- project-template:
-    name: system-config-puppet-beaker-jobs
-    description: |
-      Runs puppet beaker tests for OpenStack Infrastructure.
-      The jobs are run on Ubuntu Xenial.
-    check:
-      jobs:
-        - system-config-puppet-beaker-rspec-puppet-4-infra
-    gate:
-      jobs:
-        - system-config-puppet-beaker-rspec-puppet-4-infra