[ussuri][goal] Update contributor documentation

This patch updates/adds the contributor documentation to follow
the guidelines of the Ussuri cycle community goal[1].

[1] https://governance.openstack.org/tc/goals/selected/ussuri/project-ptl-and-contrib-docs.html
Story: #2007236
Task: #38554

Change-Id: Ifdbebe6fe4679a1a7af65e671746c98fe06d19fd

CONTRIBUTING.rst

@@ -1,98 +1,19 @@
-OpenStack-Ansible Trove
-#########################
+The source repository for this project can be found at:
 
-Contributor Guidelines
-^^^^^^^^^^^^^^^^^^^^^^
+  https://opendev.org/openstack/openstack-ansible-os_trove
 
-Filing Bugs
------------
+Pull requests submitted through GitHub are not monitored.
 
-Bugs should be filed on Launchpad, not GitHub: "https://bugs.launchpad.net
-/openstack-ansible"
+To start contributing to OpenStack, follow the steps in the contribution guide
+to set up and use Gerrit:
 
+   https://docs.openstack.org/contributors/code-and-documentation/quick-start.html
 
-When submitting a bug, or working on a bug, please ensure the following
-criteria are met:
-    * The description clearly states or describes the original problem or root
-      cause of the problem.
-    * Include historical information on how the problem was identified.
-    * Any relevant logs are included.
-    * The provided information should be totally self-contained. External
-      access to web services/sites should not be needed.
-    * Steps to reproduce the problem if possible.
+Bugs should be filed on Launchpad:
 
+   https://bugs.launchpad.net/openstack-ansible
 
-Submitting Code
----------------
+For more specific information about contributing to this repository, see the
+openstack-ansible contributor guide:
 
-Changes to the project should be submitted for review via the Gerrit tool,
-following the workflow documented at:
-"https://docs.openstack.org/infra/manual/developers.html#development-workflow"
-
-Pull requests submitted through GitHub will be ignored and closed without
-regard.
-
-
-Extra
------
-
-Tags: If it's a bug that needs fixing in a branch in addition to Master, add a
-    '\<release\>-backport-potential' tag (eg ``juno-backport-potential``).
-    There are predefined tags that will autocomplete.
-
-Status:
-    Please leave this alone, it should be New till someone triages the issue.
-
-Importance:
-    Should only be touched if it is a Blocker/Gating issue. If it is, please
-    set to High, and only use Critical if you have found a bug that can take
-    down whole infrastructures.
-
-
-Style guide
------------
-
-When creating tasks and other roles for use in Ansible please create them
-using the YAML dictionary format.
-
-Example YAML dictionary format:
-    .. code-block:: yaml
-
-        - name: The name of the tasks
-          module_name:
-            thing1: "some-stuff"
-            thing2: "some-other-stuff"
-          tags:
-            - some-tag
-            - some-other-tag
-
-
-Example **NOT** in YAML dictionary format:
-    .. code-block:: yaml
-
-        - name: The name of the tasks
-          module_name: thing1="some-stuff" thing2="some-other-stuff"
-          tags:
-            - some-tag
-            - some-other-tag
-
-
-Usage of the ">" and "|" operators should be limited to Ansible conditionals
-and command modules such as the ansible ``shell`` module.
-
-
-Issues
-------
-
-When submitting an issue, or working on an issue please ensure the following
-criteria are met:
-    * The description clearly states or describes the original problem or root
-      cause of the problem.
-    * Include historical information on how the problem was identified.
-    * Any relevant logs are included.
-    * If the issue is a bug that needs fixing in a branch other than Master,
-      add the 'backport potential' tag TO THE ISSUE (not the PR).
-    * The provided information should be totally self-contained. External
-      access to web services/sites should not be needed.
-    * If the issue is needed for a hotfix release, add the 'expedite' label.
-    * Steps to reproduce the problem if possible.
+    https://docs.openstack.org/openstack-ansible/latest/contributor/contributing.html