Use newer openstackdocstheme and reno versions

The sync from https://review.opendev.org/733244 updated to
openstackdocstheme 2.2.1 and reno 3.1.0 versions.

Set openstackdocs_pdf_link to link to PDF file. Note that
the link to the published document only works on docs.openstack.org
where the PDF file is placed in the top-level html directory. The
site-preview places the PDF in a pdf directory.

openstackdocstheme renames some variables, so follow the renames
before the next release removes them. A couple of variables are also
not needed anymore, remove them.

See also
http://lists.openstack.org/pipermail/openstack-discuss/2020-May/014971.html

Change-Id: Ic87ff263a9d3db82db1eda6e87beddb1ce64e38a

doc/source/conf.py

@@ -66,9 +66,10 @@ target_name = 'openstack-ansible-' + role_name
 title = 'OpenStack-Ansible Documentation: ' + role_name + ' role'
 
 # openstackdocstheme options
-repository_name = 'openstack/' + target_name
-bug_project = project.lower()
-bug_tag = ''
+openstackdocs_repo_name = 'openstack/' + target_name
+openstackdocs_pdf_link = True
+openstackdocs_bug_project = project.lower()
+openstackdocs_bug_tag = ''
 
 # The language for content autogenerated by Sphinx. Refer to documentation
 # for a list of supported languages.

releasenotes/source/conf.py

@@ -63,14 +63,9 @@ target_name = 'openstack-ansible-' + role_name
 title = 'OpenStack-Ansible Release Notes: ' + role_name + 'role'
 
 # openstackdocstheme options
-repository_name = 'openstack/openstack-ansible-os_horizon'
-bug_project = 'openstack-ansible-os_horizon'
-bug_tag = ''
-
-# openstackdocstheme options
-repository_name = 'openstack/' + target_name
-bug_project = project.lower()
-bug_tag = ''
+openstackdocs_repo_name = 'openstack/' + target_name
+openstackdocs_bug_project = project.lower()
+openstackdocs_bug_tag = ''
 
 # Release notes do not need a version number in the title, they
 # cover multiple releases.
@@ -158,10 +153,6 @@ html_static_path = ['_static']
 # directly to the root of the documentation.
 # html_extra_path = []
 
-# If not '', a 'Last updated on:' timestamp is inserted at every page bottom,
-# using the given strftime format.
-html_last_updated_fmt = '%Y-%m-%d %H:%M'
-
 # If true, SmartyPants will be used to convert quotes and dashes to
 # typographically correct entities.
 # html_use_smartypants = True