Add code for webhook dispatcher

A dispatcher is a new component to manage incoming webhooks from Github.
It accept new requests and manage a queue based on cluster capacity.

A capacity is defined as a number of running pipelines in certain
namespace. This simple metrics will provide a buffer mechanism for time
periods when we receive a bunk releases of operators. The mechanism
keeps pending requests in the database queue and only trigger related
pipeline in case of free capacity.

The solution is made of:
- Rest API
- Postgres database
- Dispatcher
- Capacity manager

JIRA: ISV-6108

Signed-off-by: Ales Raszka <araszka@redhat.com>

Author: Allda

operator-pipeline-images/operatorcert/webhook_dispatcher/api.py

@@ -67,7 +67,6 @@ def github_pipeline_webhook() -> Any:
     if isinstance(result, tuple):
         LOGGER.debug("GitHub webhook validation failed: %s", result)
         return jsonify(result[0]), result[1]
-
     webhook_event = convert_to_webhook_event(payload, request)
     if webhook_event is None:
         return jsonify({"status": "rejected", "message": "Unsupported event"}), 400