Replace multi-line yaml syntax for multiple lines
Replace multi-line yaml syntax for multiple lines

The multi-line yaml syntax reads better for humans on the file, however
on execution time GitLab hides it's contents on failures, which gives
little clues on what is actually failing.

Signed-off-by: Lluis Campos <9244cb41c39addfc5cf236920b776ea2820513d0@northern.tech>

mendersoftware/meta-mender-qemu