When Image.Inside() or an "agent { docker ... }" is used to docker run ... cat a docker container, it should always use the --init flag.

--init  Run an init inside the container that forwards signals and reaps processes

This creates a PID 1 --init process that is sometimes needed to properly shutdown a container with multiple processes inside it.

A lot of build containers can start up a bunch of processes that may not be properly reaped or may not properly receive TERM and QUIT signals when trying to shutdown a container.

This should fix problems like JENKINS-37769 and JENKINS-32859