Install SQLcl on Oracle Cloud Infrastructure Cloud Shell and make it work against an Autonomous Database

Cloud Shell on Oracle Cloud Infrastructure is a versatile management and development environment to access and manage Oracle Cloud Infrastructure resources. Cloud Shell comes with many tools and runtime out of the box (or rather inside the box) including OCI CLI, Java and SQL*Plus. However, the Oracle SQL Developer Command Line (SQLcl) tool — the Java-based replacement for SQL*Plus — is not part of the package (at the time of writing, 17th March 2020).