rule with redirection to external site, path not considered

Question

Dear community

I try to add autorenewal to my ssl certificates on application gateway.

I am following this tutorial:
https://intelequia.com/blog/post/1012/automating-azure-application-gateway-ssl-certificate-renewals-with-let-s-encrypt-and-azure-automation

I am not able to write the redirection correctly.
This is, what I did:

However, when I test the rediection
http://www.amasys-context.com/.well-known/acme-challenge/test.html
I am redirected here
https://sslcheckforgateway.blob.core.windows.net/public

So, how can I assure, that the path is also used in the redirection?

Thank you in advance.

Best regards
Andrea