Wrap YAML E2E tests in a function (#336)
Wrap YAML E2E tests in a function (#336)

* Wrap YAML E2E tests in a function

This makes the code cleaner, and allow failing faster on error.

* Update YAML tests execution

* report all errors, instead of stopping at the first error
* report all steps in the test for easier debugging

* Fix typo

knative/build,knative/build