Correct image path to social icons

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

app/helpers/application_helper.rb

@@ -146,8 +146,7 @@ module ApplicationHelper
 
   def authbutton(provider, size = 64)
     file_name = "#{provider.to_s.split('_').first}_#{size}.png"
-    image_tag("authbuttons/#{file_name}",
-              alt: "Sign in with #{provider.to_s.titleize}")
+    image_tag(image_path("authbuttons/#{file_name}"), alt: "Sign in with #{provider.to_s.titleize}")
   end
 
   def simple_sanitize(str)