import_ocp_project_metadata.sh uses hard coded default administrator

Describe the bug
If no project administrator is defined, the script
import_ocp_project_metadata.sh falls back to user utschig.
Other companys may want to have other default admin user.

To Reproduce
Do not specify paramter OD_PRJ_ADMINS when calling script

Expected behavior
Unclear what should be the expected behaivor.
Suggestion: Script should fail if no admin is defined

Affected version (please complete the following information):

• OpenDevStack [current master]

Additional context
Code snippet (line 135)

if [[ -z ${OD_PRJ_ADMINS} ]]; then
    # fallback
	echo ">>> no project admins set - setting clemens :)"
	echo
    OD_PRJ_ADMINS=utschig
else
	# prepend clemens' account
    OD_PRJ_ADMINS=utschig,${OD_PRJ_ADMINS}
fi

Start with ocp-templates/scripts/import_ocp_project_metadata.sh, around line 135, and reproduce the behavior by omitting OD_PRJ_ADMINS. Confirm the intended behavior with the maintainers, then ensure the script no longer relies on the hard-coded administrator and that the agreed missing-admin behavior is covered.