proxy.rb in httpx-1.3.2

- old
+ new

@@ -164,9 +164,11 @@
 
         def fetch_response(request, connections, options)
           response = super
 
           if response.is_a?(ErrorResponse) && proxy_error?(request, response)
+            return response unless @_proxy_uris
+
             @_proxy_uris.shift
 
             # return last error response if no more proxies to try
             return response if @_proxy_uris.empty?
 