[hlx strain] non-default strain doesn't work

[stefan-guggisberg]

Following the Getting Started: Strain walk through:

When changing the name in the generated .hlx/strains.yaml from default to something else (e.g. demo), hlx strain runs successfully. However, requests sent to the domain (e.g. demo.project-helix.info return 401.

changing the name to default and running hlx strain again solves the problem.

[trieloff]

A first "fix" could be some validation that checks for the existence of a default strain and makes hlx strain fail if not found.