docs(readme): Foo integration

[adamhenson]

Summary

What kind of change does this PR introduce?

Adds an integration: Foo.

Thanks in advance 🙇

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[adamhenson]

I signed it!

[googlebot]

CLAs look good, thanks!

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[patrickhulce]

Neat product!

[patrickhulce]

Could you add the note that this is a paid product? It also isn't clear if there is any sort of free trial.

[adamhenson]

Thanks for reviewing @patrickhulce. Updated in 9065b24. If you had different phrasing in mind - feel free to let me know.

[patrickhulce]

thanks for the quick response!

[patrickhulce]

Suggested change

* **[Foo](https://www.foo.software)** - Foo continuously captures performance audits with Lighthouse, notifies of change, and provides visualization. Users can choose to be notified via email, Slack and PagerDuty. A dashboard with charts show changes by day, week or month and provide detailed reports. Foo is a paid service available with tiers of pricing. Free trials aren't offered at this time, but a [demo dashboard](https://www.foo.software/demo/dashboard) is publicly available for viewing.

* **[Foo](https://www.foo.software)** - Foo continuously monitors performance with Lighthouse, monitors for changes, and provides detailed visualization. Users can receive alerts via email, Slack, and PagerDuty with daily, weekly, or monthly reports. Foo is a paid service with several tiers of pricing.

[patrickhulce]

offered a few suggestions to trim it down to the average size here, but feel free to tweak :)

[adamhenson]

Thanks @patrickhulce - I took your suggestion and trimmed it even further (removed duplicate monitors wording). Ready for re-review when you all have time. Thanks again.

[patrickhulce]

LGTM!!

[exterkamp]

LGTM

[adamhenson]

Thanks for the quick review @patrickhulce and @exterkamp.

[adamhenson]

@patrickhulce - please let me know if there’s anything else I can do to have this merged. Thanks again for your time!

[adamhenson]

Thanks for the quick turnaround everyone. Keep up the good work on this awesome project 💗