Trigger change even in select2 test helper to produce production-like behaviour

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

spec/support/select2_helper.rb

@@ -17,9 +17,9 @@ module Select2Helper
     selector = options.fetch(:from)
     if options[:multiple]
-      execute_script("$('#{selector}').select2('val', ['#{value}'], true);")
+      execute_script("$('#{selector}').select2('val', ['#{value}']).trigger('change');")
     else
-      execute_script("$('#{selector}').select2('val', '#{value}', true);")
+      execute_script("$('#{selector}').select2('val', '#{value}').trigger('change');")
     end
   end
 end