Send webmentions on a 6-hourly schedule
Because of continued instability with Netlify calling post-deploy, a safer alternative is to re-send webmentions on a schedule.
This requires tweaking the PostDeployService
to allow specifying the
threshold to send webmentions for, as we want to re-use the service for
scheduled calls, and calls from the post-deploy endpoint.
Closes #226 (closed).