[BUG] comma delimited task type list does nothing

[drew-viles]

Describe the bug
Adding a comma delimited list won't do anything as expected. This is becuase it's a hard code check if the task is set to, for example build scan or sign rather than checking if the string contains those values. It's done during the processig of the image ID before the scan and sign stages so suspect this is an oversight.

To Reproduce
Add a comma delimited list of tasks and you'll see nothing happen

Expected behavior
The tasks listed should run