Connect validator to Dataset table in LEVANTE entities

[CCuskley]

In addition to running data flows for individual active sites daily, we need to write some small functions to keep the validator in sync with our "source of truth" on which sites are live/whitelisted: the Dataset table in the LEVANTE Entites airtable. This should do at least two things (and potentially we may think of more):

• Update Open Assignments column: Using the Firestore siteId value from airtable, return documents from the administrations collection with matching siteId property. Traverse these and check whether the current date falls within the range specified in the administration dateOpened and dateClosed fields. If it does, that means the site has an open assignment. Once even one assignment is open, set Open Assignments in the Airtable to true, and break the traversal.
• Check for new sites ready for Redivis individual release: Looking at values in the Redivis individual column, flag any sites without existing Redivis individual release where this is set to true. This means the partnerships team has "switched on" individual release for this site. Use a Slack Webhook to post to slack a list of all sites awaiting individual release (cases where Redivis individual is true, but there is no release yet for that site) to prompt the team to prepare the release.

[mikabr]

I think it makes sense to add a layer here where the airtable table is synced to redivis (much like the item metadata) and have the validator pull from there.