I am having trouble installing libzmq3-dev on Ubuntu 16.04 on GitHub Actions. This may be a user error on my part because I do not run into an error when I install it on my local Ubuntu machine. I would appreciate troubleshooting advice, e.g. libraries I should be installing prior to libzmq3-dev on GHA machines specifically.
I posted a minimal reproducible example to https://github.com/wlandau/libzmq-reprex/runs/2521101152. Related: Cannot install libzmq3-dev on ubuntu 19.04.
Run sudo apt-get install libzmq3-dev
Reading package lists...
Building dependency tree...
Reading state information...
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:
The following packages have unmet dependencies:
libzmq3-dev : Depends: libzmq5 (= 4.1.4-7ubuntu0.1) but 4.3.1-5+ubuntu16.04.1+deb.sury.org+1 is to be installed
E: Unable to correct problems, you have held broken packages.
Error: Process completed with exit code 100.
