Currently, custom startup scripts are only supported within the cli container.
A startup script can be used to execute actions whenever a container is started. This can be ensuring a service
is installed, making sure a file is compiled, or regenerating a key. This file is located within the projects
.docksal/services/cli directory and should be named startup.sh. All commands in the file will run at the time
of container startup. Make sure this file has execute permissions or it will not run.