Clean up `DictLiteral` and `DictComprehension` emission logic (#64953)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/64953
Test Plan: Imported from OSS
Reviewed By: jamesr66a
Differential Revision: D30914687
Pulled By: ansley
fbshipit-source-id: ab9b9192a29f05b90c113c678e7c795bc087dc99