Merge pull request #1135 from alphagov/dependabot/bundler/mongoid-7.5.4

Bump mongoid from 7.5.3 to 7.5.4

Author: Al Davidson

Gemfile.lock

@@ -199,7 +199,7 @@ GEM
     minitest (5.19.0)
     mongo (2.15.0)
       bson (>= 4.8.2, < 5.0.0)
-    mongoid (7.5.3)
+    mongoid (7.5.4)
       activemodel (>= 5.1, < 7.1, != 7.0.0)
       mongo (>= 2.10.5, < 3.0.0)
       ruby2_keywords (~> 0.0.5)