74943a2aa1
Switch to openstackdocstheme 2.2.0 and reno 3.1.0 versions. Using these versions will allow especially: * Linking from HTML to PDF document * Allow parallel building of documents * Fix some rendering problems Update Sphinx version as well. Add configuration for openstackdocstheme 'report a bug'. Depends-On: https://review.opendev.org/728938 Change-Id: I0938ef80ec161607e7c4b2a4a846f1b32e7614e3