Add evaluation details to finally hook stage.

Notes

This breaks the signature of the finally stages based on this spec enhancement. It is not considered a breaking change to the SDK because hooks are marked as experimental in the spec, and the change has no impact on known hooks.

This has been done in other repos:

• Add evaluation details to finally hook stage js-sdk#1109
• Add evaluation details to finally hook stage java-sdk#1246

Acceptance criteria:

• finally hook stage modified
• associated tests

Follow ups:

• update hooks in the contribs repo