Scripts `init/bash` and `init/lmod/*` are actually templates

[ocaisa]

This was raised in #153

Value replacements are done in

software-layer-scripts/install_scripts.sh

Lines 235 to 240 in 6e27876

	sed_update_if_changed "s/__EESSI_VERSION_DEFAULT__/${EESSI_VERSION}/g" ${INSTALL_PREFIX}/init/eessi_defaults
	# replace placeholder for default EESSI version in Lmod init scripts
	for shell in $(ls ${INSTALL_PREFIX}/init/lmod); do
	sed_update_if_changed "s/__EESSI_VERSION_DEFAULT__/${EESSI_VERSION}/g" ${INSTALL_PREFIX}/init/lmod/${shell}
	done

This would change a few things in our CI, and make things a little harder to test directly from the repo so I leave it as an issue to follow up on.