Avoid FOUC when using CSS modules in dev

[DrLoopFall]

Fixes #5019

Importing CSS modules causes flash of unstyled content, as an object is returned from Vite causing it to be injected as [object Object] inside the style tag.
Importing with ?inline, allows Vite to returns the CSS as string which can be used inside the style tag.

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[benmccann]

Thank you @DrLoopFall!