Order downloads by rubygem_id before updating ES index
Order downloads by rubygem_id before updating ES index

`where(rubygem_id: rubygem_ids, version_id: 0)` does not gurantee that
it will preserve order of rubygem_ids array.
It was causing initial downloads count(used for ES index update) to
be mixed up.

kbrock/rubygems.org,JuanitoFatas/rubygems.org,kbrock/rubygems.org,rubygems/rubygems.org,JuanitoFatas/rubygems.org,algolia/rubygems.org,algolia/rubygems.org,kbrock/rubygems.org,rubygems/rubygems.org,sonalkr132/rubygems.org,sonalkr132/rubygems.org,rubygems/rubygems.org,JuanitoFatas/rubygems.org,JuanitoFatas/rubygems.org,algolia/rubygems.org,rubygems/rubygems.org,sonalkr132/rubygems.org,sonalkr132/rubygems.org,kbrock/rubygems.org,algolia/rubygems.org