Eager load award emoji on notes

This commit eager loads the award emoji on both the issues and the MRs.
When loading an issue with 108 comments this reduces the query count by
327 queries. On a merge request with the same amount of comments this
saves 148 queries. The large difference is not clear to me at this
point and the total query count is still huge with 387 and 1034
respectively. The biggest problem however, remains the calculation of
participants.