Merge pull request #1003 from alphagov/ci-bump-govuk-chat-private-1873a77

Bump govuk_chat_private to 1873a77

Author: davidgisbey

Gemfile.lock

@@ -1,6 +1,6 @@
 GIT
   remote: https://github.com/alphagov/govuk_chat_private.git
-  revision: c2dc42c401c836caae13703c9b6ef163b64e9052
+  revision: 1873a771663d738df7d01db2fe49840546973076
   specs:
     govuk_chat_private (0.0.1)
       activesupport (>= 8)