Use quotes for circular field definitions

app/graphql/types/project_type.rb

@@ -108,7 +108,9 @@ module Types
     field :suggestion_commit_message, GraphQL::Types::String, null: true,
           description: 'Commit message used to apply merge request suggestions.'
 
-    field :group, Types::GroupType, null: true,
+    # No, the quotes are not a typo. Used to get around circular dependencies.
+    # See https://gitlab.com/gitlab-org/gitlab/-/merge_requests/27536#note_871009675
+    field :group, 'Types::GroupType', null: true,
           description: 'Group of the project.'
     field :namespace, Types::NamespaceType, null: true,
           description: 'Namespace of the project.'

app/graphql/types/todo_type.rb

@@ -18,7 +18,7 @@ module Types
           null: true,
           authorize: :read_project
 
-    field :group, Types::GroupType,
+    field :group, 'Types::GroupType',
           description: 'Group this to-do item is associated with.',
           null: true,
           authorize: :read_group

ee/app/graphql/types/epic_type.rb

@@ -34,9 +34,9 @@ module Types
 
     field :author, Types::UserType, null: false,
           description: 'Author of the epic.'
-    field :group, GroupType, null: false,
+    field :group, 'Types::GroupType', null: false,
           description: 'Group to which the epic belongs.'
-    field :parent, EpicType, null: true,
+    field :parent, Types::EpicType, null: true,
           description: 'Parent epic of the epic.'
 
     field :start_date, Types::TimeType, null: true,