Allow ADD with getting files from a URL

[inductor]

Description

FATAL	- CIS-DI-0009: Use COPY instead of ADD in Dockerfile
	* Use COPY : ADD https://github.com/jwilder/docker-gen/releases/download/0.7.4/docker-gen-linux-amd64-0.7.4.tar.gz /tmp/
	* Use COPY : ADD https://github.com/just-containers/s6-overlay/releases/download/v1.22.1.0/s6-overlay-amd64.tar.gz /tmp/
	* Use COPY : ADD https://raw.githubusercontent.com/diafygi/acme-tiny/5350420d35177eda733d85096433a24e55f8d00e/acme_tiny.py /bin/acme_tiny

This case ADD must be used.

What did you expect to happen?

What happened instead?

Output of run with -debug:

(paste your output here)

Output of dockle -v:

(paste your output here)

Additional details (base image name, container registry info...):

[tomoyamachi]

OK, I will check target file format when check ADD.

[tomoyamachi]

It may take a while. Please use -i CIS-DI-0009 flag so far.

[tomoyamachi]

It is possible to detect ADD with URL if using buildkit.

[olafurnielsen]

It is possible to detect ADD with URL if using buildkit.

Can you elaborate? I'm getting this fatal despite using buildkit. Are there any extra configuration needed?