Grant access for important docs based on Slack channel membership

[patcon]

I just realized that many organizers didn't and don't have access to our password doc.

Since being invited to #organizing-priv as a mark of trusted membership, we could use this to grant access, assuming people use their Google-friendly email for our Slack.

When someone joins a specific private channel #organizing-priv, it would be great to automatically grant access.

• this could run nightly
• it should announce that it's added people in #organizing-priv and #organizing-open, so it's not forgotten that this is happening
• would be great if it was on-demand right after adding, but that's a little harder, so maybe later.

Docs to grants:

• Edit access on GDrive folder hierarchy (normally publicly viewable)
• Edit access on passwords GDoc (normally private)

[patcon]

Working on this: https://github.com/patcon/civictechto-scripts/tree/7-grant-gdrive-access