Option to bypass generating Send when mocking async functions

Currently when passing #[automock] to a trait with async functions, it automatically generates Send for its return value to ensure thread safety. However, I am working on an async runtime that guarantees to be run on a single thread, so it does not require Send for its return value.

I'd like to request a feature to add a flag in #[automock] or something similar to not generate Send for mocked functions' return value.