Merge pull request #895 from 6br/fix_webpack4

Improve the condition of webpacker major version

Author: ttanimichi

lib/react/server_rendering/webpacker_manifest_container.rb

@@ -77,7 +77,7 @@ def config
         def file_path path
           manifest.lookup_path(path)
         end
-      elsif MAJOR == 3
+      elsif MAJOR >= 3
         def file_path path
           ::Rails.root.join('public', manifest.lookup(path)[1..-1])
         end