feat: support files other than js to be ESM

[SimenB]

Summary

Fixes #9860. See that issue for some discussion.

We could have an option somewhere for transformers to decide, but then we'd have have some forking logic in jest-runtime. Just having a top level option seems easier to reason about to me. Open to being convinced otherwise, tho! 👍

Test plan

E2E test added, plus unit tests for the config verification.

[thymikee]

If we're running in ESM mode, shouldn't we treat all moduleFileExtensions (maybe except json) as modules then? I just wonder if we could get away without adding a new config option.

[SimenB]

How would ESM mode be "triggered"? Also, it's perfectly fine to use import on CJS from ESM or import() on ESM from CJS so being in "one mode" is not really possible unless your entire dependency tree is uniform.

[SimenB]

I'm thinking we can land this so people can test this, and if we figure out a better approach in the future we can revert

[ahnpnl]

I think custom transformer guidance also needs updating ?

[SimenB]

I think custom transformer guidance also needs updating ?

Done in #10834 - this PR doesn't change that fact (i.e. use supportsStaticESM to check if import should be used - this PR just allows the user to pass config which makes sure that flag is set to true instead of false for non-JS)

[github-actions]

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