YAML tags for environment block

The environment tag is intended to be used to inject a global environment configuration into steps, services and secret containers. Control of which container types get the injected environment settings is available via the metadata block.

# This document is displaying using the environment tag with a map syntax.
# Additionally, you can also use array syntax where the items in
# they array are of pattern HELLO="Hello, Vela!"
  HELLO: "Hello, Vela!"