Handle binary data properly in Geo transfer download

lib/gitlab/geo/transfer.rb

@@ -60,7 +60,7 @@ module Gitlab
         file_size = -1
 
         begin
-          File.open(filename, "w") do |file|
+          File.open(filename, "wb") do |file|
             response = HTTParty.get(url, headers: req_header, stream_body: true) do |fragment|
               file.write(fragment)
             end

spec/lib/gitlab/geo/transfer_spec.rb

@@ -9,7 +9,7 @@ describe Gitlab::Geo::Transfer do
   let(:size) { File.stat(lfs_object.file.path).size }
 
   before do
-    allow(File).to receive(:open).with(lfs_object.file.path, "w").and_yield(content)
+    allow(File).to receive(:open).with(lfs_object.file.path, "wb").and_yield(content)
   end
 
   subject do