ingest/nextstrain-automation: revisit Slack notification rules

[joverlee521]

Follow up to #342

The Slack notification rules currently point to incorrect S3 files

• The ppx.ndjson.zst file does not exist on S3, so we do not get any "New records" notifications. This needs to be updated to ppx_with_restricted.ndjson.zst
• The local OPEN+RESTRICTED results/metadata.tsv is being compared to the OPEN metadata.tsv.zst on S3, so we will always receive diffs of the RESTRICTED data. This needs to be updated to metadata_with_restricted.tsv.zst.

These are easy fixes, but I'm also questioning whether these Slack notifications are still useful. If not, we should no longer maintain the rules and just remove them completely.

[victorlin]

I'm also questioning whether these Slack notifications are still useful.

I've never actively followed these, and seems like we're doing fine without it on most other automated pathogen repos. But sounds like it was useful for discovering #343?

[joverlee521]

But #344 (comment) it was useful for discovering #343?

Ah, that was just a fluke due to this bug. If the Slack notifications were correctly updated, they would not have flagged the issue either.