fix: throws/reject typings

[Julien-R44]

those typings were way too strict
before the PR, TS complained about this :

// TS complains because the function doesnt return `void`
await assert.rejects(() => myFunctionReturningAString())

// TS complains when using an Error constructor that accepts args other than raw Error,
// like the one from poppins/exceptions
await assert.rejects(() => something(), E_MY_ERROR)