[jest] fix type inference for Mocked & mockResolvedValue/mockRejectedValue

[antoinebrault]

Follow-up of #32579 (comment) , fixes #32890

Fixed Mocked interface & mockResolvedValue/mockRejectedValue

Breaking Change

With types inferred, mockResolvedValue(), mockRejectedValue() will not compile if they are used on a function not returning a Promise.
e.g.

class Test {
    method(x: string): string {
        return x;
    }
}
const test: Mocked<Test> = new Test() as any;

// this doesn't compile, because mockImplementation expects () => string
test.method.mockImplementation(() => Promise.resolve(''));

// this shouldn't compile either because mockResolvedValue() is sugar for mockImplementation(() => Promise.resolve());
test.method.mockResolvedValue('');

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[antoinebrault]

@Chris-V updated code to be consistent with mockImplementation() & added tests

[typescript-bot]

@antoinebrault Thank you for submitting this PR!

🔔 @NoHomey @jwbay @asvetliakov @alexjoverm @epicallan @ikatyang @wsmd @JamieMason @douglasduteil @ahnpnl @JoshuaKGoldberg @UselessPickles @r3nya @Hotell @sebald @andys8 @aldentaylor - please review this PR in the next few days. Be sure to explicitly select Approve or Request Changes in the GitHub UI so I know what's going on.

If no reviewer appears after a week, a DefinitelyTyped maintainer will review the PR instead.

[Chris-V]

Thank you! We had several helpers types in our code base to improve type-safety with jest. This will help us get rid of most of them!

[fgrandel]

I provided an alternative proposal to solve this issue just for consideration, see #32898 - Please feel free to close this PR if you prefer your own solution. :-)

[fgrandel]

Proposal to add additional tests + (optional) proposal to introduce correct (i.e. more strongly typed) signature for jest.fn, Mock, etc. Feel free to go along w/o the proposed changes if you think I'm off track. :-)

[typescript-bot]

@antoinebrault Unfortunately, this pull request currently has a merge conflict 😥. Please update your PR branch to be up-to-date with respect to master. Have a nice day!

[typescript-bot]

🔔 @Jerico-Dev @jwbay - Thanks for your review of this PR! Can you please look at the new code and update your review status if appropriate?

[typescript-bot]

🔔 @jwbay - Thanks for your review of this PR! Can you please look at the new code and update your review status if appropriate?

[typescript-bot]

A definition owner has approved this PR ⭐️. A maintainer will merge this PR shortly. If it shouldn't be merged yet, please leave a comment saying so and we'll wait. Thank you for your contribution to DefinitelyTyped!

[typescript-bot]

I just published @types/jest@24.0.2 to npm.

[typescript-bot]

I just published @types/jest-when@1.1.4 to npm.