Added award emoji to the epics public API

What does this MR do?

To allow for epics to use the new Vue award emoji block we need epics to have the award emoji API endpoint.

This merge request is a prerequisite for that to happen by adding award emoji to the epics API endpoints. This is also done in a way to also allow for us to add this to normal snippets as well.

Screenshots (strongly suggested)

Does this MR meet the acceptance criteria?

Conformity

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