Wait for index swap before sending BS alerts

[nickdos]

For consideration/evaluation only

Following a discussion about the issue of iNat images not always appearing in BS emails, it was suggested that the code perform a check against image-service and biocache before proceeding to sending the emails. If the check fails, then the job is delayed an hour and the check is re-run. If it fails more than (say) 5 times, then it should "fail out" and no email will be sent until the next scheduled run (1 week). Optionally sending an email to an admin saying the job was cancelled due to images not being avilable.

Suggested checks:

1. Check image loading has finished via https://images.ala.org.au/ws/batch/dataresource/dr1411 (not needed?)
2. Send a query to the image-service for the most recently added image from iNat (DR1411), saving the UUID for that image. The creation date for the image should be in the last 5 days (sub check?)
3. Send a query to biocache-ws with the image UUID. If no results, then sleep for 1 hour and try again then. If a record is returned, then proceed with the biosecurity alerts.