Revert multipart URL optimization for AWS S3

https://gitlab.com/gitlab-org/gitlab/-/merge_requests/49482 omitted the
multipart upload URLs for Workhorse if the S3 client were used, but
Rails doesn't actually control whether Workhorse will use the S3
client. For example, previously if Workhorse detected a blank region, it
would not use the native client.

Since the multipart URLs were not available, Workhorse would attempt to
use the PutObject API for uploads, which might fail if chunked encodings
were used.

We now always include these multipart URLs to be safe.

Relates to https://gitlab.com/gitlab-org/gitlab-workhorse/-/issues/292

changelogs/unreleased/sh-revert-multipart-upload-optimization.yml

+---
+title: Revert multipart URL optimization for AWS S3
+merge_request: 52561
+author:
+type: fixed

lib/object_storage/direct_upload.rb

@@ -206,7 +206,7 @@ module ObjectStorage
     end
 
     def requires_multipart_upload?
-      config.aws? && !has_length && !use_workhorse_s3_client?
+      config.aws? && !has_length
     end
 
     def upload_id

spec/lib/object_storage/direct_upload_spec.rb

@@ -162,10 +162,6 @@ RSpec.describe ObjectStorage::DirectUpload do
         it 'enables the Workhorse client' do
           expect(subject[:UseWorkhorseClient]).to be true
         end
-
-        it 'omits the multipart upload URLs' do
-          expect(subject).not_to include(:MultipartUpload)
-        end
       end
 
       context 'when only server side encryption is used' do