Fix multilib error in centos docker container

As of the time of writing, you may get an error like this when installing openssl inside a docker container with CentOS image:

Error:  Multilib version problems found. This often means that the root
       cause is something else and multilib version checking is just
       pointing out that there is a problem. (...)

You can fix this by enabling CentOSPlus repo in your Dockerfile with:

sed -i '/^\[centosplus\]$/,/^\[/ s/^enabled=0$/enabled=1/' /etc/yum.repos.d/CentOS-Base.repo

Then do a regular yum install openssl-devel and it should work!

NOTE: Get rid of the RUN if you are not in a Dockerfile but in a shell script or session.