Update gitter-services v1.21.0

Open username-removed-892863 requested to merge feature/update-service-integrations into develop

Update gitter-services v1.21.0 (integrations)

  • Discourse integration
  • The Bug Genie integration

See companion gitter-webhooks-handler PR, https://github.com/gitterHQ/gitter-webhooks-handler/pull/7

Edited by username-removed-892863