fix(types): bench.reporters no longer gives type errors when passing file name string paths

[Bertie690]

Description

Fixes a oneline typing error inside vitest/node that caused TypeScript to produce type errors complain about bench.reporters not accepting arbitrary strings for reporter file paths. Vitest processes them just fine, but the type was overly restrictive and led to type errors that contradicted existing docs.

Fixes #9692

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Tests

N/A - this is fixing a type bug

Documentation

N/A - this is fixing a bug

Changesets

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