Support for defining target in config file

[brandtkeller]

Is your feature request related to a problem? Please describe.

Ability to set target in a lula-config.yaml file such that lula defaults to a set target during validate and evaluate operations

Describe the solution you'd like

• Given target is specified in a lula-config.yaml
• When validate/evaluate are executed
• Then the target defined is used in place of the flag

Additional context

useful for implementations where specifying a target may be difficult (IE Big Bang pipelines)

Expected Deliverable

Update validate and evaluate to use target when defined in a lula-config.yaml