Delete temp migration file in test and ignore it

.gitignore

@@ -7,3 +7,4 @@
 /pkg/
 /spec/reports/
 /tmp/
+/test/tmp/

test/tmp/db/migrate/20170315192300_create_key_values_table.rb

@@ -1,19 +0,0 @@
-class CreateKeyValuesTable < ActiveRecord::Migration
-  def self.up
-    create_table :key_values do |t|
-      t.string :key, :null => false
-      t.binary :value, :null => false
-      t.datetime :expires_at, :null => true
-      t.timestamps :null => false
-    end
-
-    add_index :key_values, :key, :unique => true
-    add_index :key_values, :expires_at
-
-    change_column :key_values, :id, "bigint(20) NOT NULL AUTO_INCREMENT"
-  end
-
-  def self.down
-    drop_table :key_values
-  end
-end