GoUsers: add Snyk and Circle

Change-Id: I242d4d0308c63b89adef18cefd7137efbb549a37
Reviewed-on: https://go-review.googlesource.com/c/wiki/+/657875
Commit-Queue: Ian Lance Taylor <[email protected]>
Auto-Submit: Ian Lance Taylor <[email protected]>
Reviewed-by: Ian Lance Taylor <[email protected]>

Author: seankhliao

GoUsers.md

@@ -1519,6 +1519,7 @@ Certificate Expiry Monitor Controller monitors the expiration of TLS certificate
   * [Chatlio](https://chatlio.com)
   * [Chubbs Solutions](https://chubbs.solutions) - Progressive Tech (APIs).
   * [Cisco](https://cisco.com/) - [github](https://github.com/cisco?utf8=%E2%9C%93&q=&type=&language=go)
+  * [Circle](https://www.circle.com/)
   * [CircleCI](https://circleci.com)
   * [Circonus](https://www.circonus.com)
   * [Clearblade](http://clearblade.com/) - [github](https://github.com/ClearBlade/Go-SDK)
@@ -1775,11 +1776,12 @@ Certificate Expiry Monitor Controller monitors the expiration of TLS certificate
   * [Showyou](http://www.showyou.com) [source](https://plus.google.com/101522949595361604155/posts/8n4CSePMwgV)
   * [Shutterfly](http://www.shutterfly.com)
   * [SignalFx](https://signalfx.com/) - [blog](http://blog.signalfx.com/why-the-signalfx-metric-proxy-is-written-in-go)
+  * [Skimlinks](http://www.skimlinks.com) [blog](https://speakerdeck.com/rjohnsondev/go-at-skimlinks)
   * [Slack](https://slack.com) - [blog](https://slack.engineering/scaling-slacks-job-queue-687222e9d100)
   * [SlingTV](https://www.sling.com)
   * [SmartyStreets](http://smartystreets.com) - [github](https://github.com/smartystreets), [blog](https://smartystreets.com/blog)
   * [SmugMug](http://www.smugmug.com/) - [blog](http://sorcery.smugmug.com/2012/04/06/deriving-json-types-in-go/)
-  * [Skimlinks](http://www.skimlinks.com) [blog](https://speakerdeck.com/rjohnsondev/go-at-skimlinks)
+  * [Snyk](https://snyk.io/)
   * [Social Blade](https://socialblade.com)
   * [Sorint.US](https://www.sorintlab.com) - [github](https://github.com/sorintlab)
   * [SoundCloud](http://soundcloud.com) - [blog](http://backstage.soundcloud.com/2012/07/go-at-soundcloud/)