Fix some linting issues

Author: xjunior

lib/departure/configuration.rb

@@ -19,11 +19,11 @@ def error_log_path
     end
 
     def adapter=(name)
-      if SUPPORTED_ADAPTERS.include?(name)
-        @adapter = name
-      else
+      unless SUPPORTED_ADAPTERS.include?(name)
         raise ArgumentError, "Supported Departure adapters are #{SUPPORTED_ADAPTERS.inspect}"
       end
+
+      @adapter = name
     end
 
     private

spec/departure/runner_spec.rb

@@ -1,8 +1,8 @@
 require 'spec_helper'
 require 'tempfile'
 
-require "active_record/connection_adapters/mysql2_adapter"
-require "active_record/connection_adapters/trilogy_adapter"
+require 'active_record/connection_adapters/mysql2_adapter'
+require 'active_record/connection_adapters/trilogy_adapter'
 
 describe Departure::Runner do
   shared_examples_for Departure::Runner do |adapter|