Remove legacy queries to find replicated uploads to expire

This commit removes the legacy to find replicated uploads
to expire since we made Foreign Data Wrapper (FDW) a hard
requirement for Geo on GitLab 12.0.

ee/app/finders/geo/expire_uploads_finder.rb

@@ -5,11 +5,7 @@ module Geo
     UPLOAD_TYPE = 'file'
 
     def find_project_uploads(project)
-      if Gitlab::Geo::Fdw.enabled?
-        Geo::Fdw::Upload.for_model_with_type(project, UPLOAD_TYPE)
-      else
-        legacy_find_project_uploads(project)
-      end
+      Geo::Fdw::Upload.for_model_with_type(project, UPLOAD_TYPE)
     end
 
     def find_file_registries_uploads(project)
@@ -39,20 +35,5 @@ module Geo
       SQL
     end
     # rubocop:enable CodeReuse/ActiveRecord
-
-    # rubocop:disable CodeReuse/ActiveRecord
-    def legacy_find_project_uploads(project)
-      file_registry_ids = legacy_find_file_registries_uploads(project).pluck(:file_id)
-      return Upload.none if file_registry_ids.empty?
-
-      values_sql = file_registry_ids.map { |f_id| "(#{f_id})" }.join(',')
-
-      Upload.joins(<<~SQL)
-        JOIN (VALUES #{values_sql})
-          AS file_registry (file_id)
-          ON (file_registry.file_id = uploads.id)
-      SQL
-    end
-    # rubocop:enable CodeReuse/ActiveRecord
   end
 end

ee/spec/finders/geo/expire_uploads_finder_spec.rb

@@ -57,35 +57,6 @@ describe Geo::ExpireUploadsFinder, :geo do
       stub_fdw_disabled
     end
 
-    describe '#find_project_uploads' do
-      context 'filtering per project uploads' do
-        it 'returns only objects associated with the project' do
-          other_upload = create(:upload, :issuable_upload)
-          upload = create(:upload, :issuable_upload, model: project)
-          create(:geo_file_registry, file_id: upload.id)
-          create(:geo_file_registry, file_id: other_upload.id)
-
-          uploads = subject.find_project_uploads(project)
-
-          expect(uploads.count).to eq(1)
-          expect(uploads.first.id).to eq(upload.id)
-        end
-      end
-
-      context 'filtering replicated uploads only' do
-        it 'returns only replicated or to be replicated objects' do
-          create(:upload, :issuable_upload, model: project)
-          upload = create(:upload, :issuable_upload, model: project)
-          create(:geo_file_registry, file_id: upload.id, success: false)
-
-          uploads = subject.find_project_uploads(project)
-
-          expect(uploads.count).to eq(1)
-          expect(uploads.first.id).to eq(upload.id)
-        end
-      end
-    end
-
     describe '#find_file_registries_uploads' do
       context 'filtering per project uploads' do
         it 'returns only objects associated with the project' do