Find a way to add more vendor positions and update the positions and concerns automatically

[captainbrosset]

Vendor positions are mapped in standard-positions.json. The mapping was done manually. In this issue, we should map more positions (if the first mapping missed some of them, which I'm sure of), and figure out a way to continue mapping more automatically.

Secondly, we should run the update-standard-positions.js script automatically (perhaps monthly) to make sure the list of positions and concerns are always up to date.

[captainbrosset]

Mozilla just updated the way they handle positions on their repository. See mozilla/standards-positions#1034.

The summary is that they now have a new dashboard showing their positions, and the data for the dashboard comes from issues on the repo and (optionally) additional data in a YAML file.
They also have a build step that generates the dashboard site, and the build step involves generating a merged JSON file with all of the data we need:

https://github.com/mozilla/standards-positions/blob/gh-pages/merged-data.json

We could therefore update the update-standard-positions.js script to pull data from that file instead. Interestingly, that file also contains a rationale field which would be useful to show in the explorer.