Add support for mapped dependency outputs

[kichristensen]

What does this change

Implements support for dependency output mapping in Dependencies V2.
This is precursor to #2662 as it requires that dependency outputs can be mapped and templated. In this implementation only the "old" format is implemented, ${outputs.OUTPUT_NAME} is not supported yet, but will be implemented in a follow-up PR, where the documentation also would be updated.

What issue does it fix

Closes no issues but is a precursor to #2662

Notes for the reviewer

Checklist

• Did you write tests?
• Did you write documentation?
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[schristoff]

I appreciate you taking action on this :)