Configuration settings for facebook provider

[SidharthBansal]

Make sure these boxes are checked before your pull request (PR) is ready to be reviewed and merged. Thanks!

• tests pass -- look for a green checkbox ✔️ a few minutes after opening your PR -- or run tests locally with rake test
• code is in uniquely-named feature branch and has no merge conflicts
• PR is descriptively titled
• PR body includes fixes #0000-style reference to original issue #
• ask @publiclab/reviewers for help, in a comment below

We're happy to help you get this ready -- don't be afraid to ask for help, and don't be discouraged if your tests fail at first!

If tests do fail, click on the red X to learn why by reading the logs.

Please be sure you've reviewed our contribution guidelines at https://publiclab.org/contributing-to-public-lab-software

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Thanks!

[plotsbot]

	1 Warning
⚠️	It looks like you merged from master in this pull request. Please rebase to get rid of the merge commits – you may want to rewind the master branch and rebase instead of merging in from master, which can cause problems when accepting new code!

	2 Messages
📖	@SidharthBansal Thank you for your pull request! I’m here to help with some tips and recommendations. Please take a look at the list provided and help us review and accept your contribution! And don’t be discouraged if you see errors – we’re here to help.
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[SidharthBansal]

@jywarren can we merge this? It is ready to be merged

[jywarren]

👍🏼