FileAccessor#resource_bundles should exclude asset catalogs

Even that could be fixed by appropriate configuration, there is just no case, where it would make sense to have an asset catalog inside of an resource bundle.

lib/cocoapods/sandbox/file_accessor.rb

@@ -167,7 +167,7 @@ module Pod
       def resource_bundles
         result = {}
         spec_consumer.resource_bundles.each do |name, file_patterns|
-          paths = expanded_paths(file_patterns, :include_dirs => true)
+          paths = expanded_paths(file_patterns, :include_dirs => true, :exclude_patterns => %w(**/*.xcassets))
           result[name] = paths
         end
         result