Make create_between consistent for versions with same created_at.

app/models/version.rb

@@ -169,8 +169,9 @@ def self.rubygem_name_for(full_name)
     find_by(full_name: full_name)&.rubygem&.name
   end
 
+  # id is added to ORDER to return stable results for gems pushed at the same time
   def self.created_between(start_time, end_time)
-    where(created_at: start_time..end_time).order(:created_at)
+    where(created_at: start_time..end_time).order(:created_at, :id)
   end
 
   def platformed?

test/models/version_test.rb

@@ -1036,11 +1036,13 @@ class VersionTest < ActiveSupport::TestCase
       @end_time = Time.zone.parse("2017-11-10")
     end
 
-    should "return versions created in the given range" do
-      @version.created_at = Time.zone.parse("2017-10-20")
+    should "return versions created in the given range ordered by date and id" do
+      created_at = Time.zone.parse("2017-10-20")
+      other_version = create(:version, created_at: created_at)
+      @version.created_at = created_at
       @version.save!
 
-      assert_contains Version.created_between(@start_time, @end_time), @version
+      assert_equal [other_version.id, @version.id], Version.created_between(@start_time, @end_time).map(&:id)
     end
 
     should "NOT return versions created before the range begins" do