vitest --changed is goated now if it ran as fast as bun...

@douges Here's `bun test --changed` (along with `--changed --watch support) github.com/oven-sh/bun/pu…

FWIW 1. Vitest has test isolation on by default while Bun does not (AFAIK not even well supported). This means you are sacrificing correctness / requires manual cleanup when running tests with Bun. 2. Without isolation Vitest actually runs significantly faster than Bun when there are many test files (Bun has no file-level parallelism for tests).