[JIT] Fix TupleType.annotation_str to conform to `typing` module syntax for empty tuple type (#54641)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/54641
Test Plan: Imported from OSS
Reviewed By: SplitInfinity
Differential Revision: D27314173
Pulled By: jamesr66a
fbshipit-source-id: 13c6e6b571672adc443429f59f3b30aae356c03d
