Spark 2 on debian 10 (buster)

Hm, worked fine on my install in the end…
Wait, do you have a VPN turned on? If so, try turning that off and redoing the install…

I have encountered this same problem using an RPi2B. I am much less adept at troubleshooting this than the original poster.

sudo -E sh -c apt-get install -y -qq --no-install-recommends docker-ce >/dev/null
E: Sub-process /usr/bin/dpkg returned an error code (1)
Command ‘curl -sL []( | sh’ returned non-zero exit status 100.

This works now after rebooting and following the steps at BrewBlox Basic questions