Add a link to the workflow execution in the library update commit

[josecelano]

When a worker executes a job and updates the website you can easily check what was added, for example:

3435d8e

but if something was wrong you can't easily find the workflow execution. We can include in the job payload a link to the workflow execution id.

EDIT: we have plans to add metadata to the commit body on the GitQueue roadmap. If we add that information always, we do not need to include it on the website message payload. It would be always available.

EDIT: we agreed here that it makes more sense to put the workflow URL in the user payload, not in the queue metatada. Because the queue could be used with other infrastructures in the future.