chore: fix _feature being returned in allVariables

Author: jsalaber

lib/devcycle-ruby-server-sdk/api/client.rb

@@ -353,7 +353,7 @@ def all_variables(user, opts = {})
 
       if local_bucketing_initialized? && @local_bucketing.has_config
         bucketed_config = @local_bucketing.generate_bucketed_config(user)
-        bucketed_config.variables
+        bucketed_config.variables.reject { |key, _| key.start_with?('_feature') }
       else
         {}
       end