Rename ProjectEntity to IssuableEntity

lib/api/entities.rb

@@ -491,7 +491,7 @@ module API
       end
     end
-    class ProjectEntity < Grape::Entity
+    class IssuableEntity < Grape::Entity
       expose :id, :iid
       expose(:project_id) { |entity| entity&.project.try(:id) }
       expose :title, :description
@@ -544,7 +544,7 @@ module API
       end
     end
-    class IssueBasic < ProjectEntity
+    class IssueBasic < IssuableEntity
       expose :closed_at
       expose :closed_by, using: Entities::UserBasic
@@ -650,14 +650,14 @@ module API
       end
     end
-    class MergeRequestSimple < ProjectEntity
+    class MergeRequestSimple < IssuableEntity
       expose :title
       expose :web_url do |merge_request, options|
         Gitlab::UrlBuilder.build(merge_request)
       end
     end
-    class MergeRequestBasic < ProjectEntity
+    class MergeRequestBasic < IssuableEntity
       expose :merged_by, using: Entities::UserBasic do |merge_request, _options|
         merge_request.metrics&.merged_by
       end

lib/api/import_github.rb

@@ -28,7 +28,7 @@ module API
     desc 'Import a GitHub project' do
       detail 'This feature was introduced in GitLab 11.3.4.'
-      success Entities::ProjectEntity
+      success ::ProjectEntity
     end
     params do
       requires :personal_access_token, type: String, desc: 'GitHub personal access token'