Update octavia-tempest-plugin configref

This patch updates the octavia-tempest-plugin configuration reference
documentation to only include octavia-tempest-plugin specific
configuration options.
This simplifies our documentation and means bugs in other plugins will
not break our configuration reference docs job.

It also re-enables the docs job, disabled in a previous patch.

Change-Id: I53d81ca7bd910838927d594bfb0e72320b9d1ec6
diff --git a/octavia_tempest_plugin/opts.py b/octavia_tempest_plugin/opts.py
new file mode 100644
index 0000000..2385035
--- /dev/null
+++ b/octavia_tempest_plugin/opts.py
@@ -0,0 +1,21 @@
+# Licensed under the Apache License, Version 2.0 (the "License"); you may not
+# use this file except in compliance with the License. You may obtain a copy
+# of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import octavia_tempest_plugin.config
+
+
+def list_opts():
+    return [
+        ('load_balancer', octavia_tempest_plugin.config.OctaviaGroup),
+        ('loadbalancer-feature-enabled',
+         octavia_tempest_plugin.config.LBFeatureEnabledGroup),
+    ]