Change vite config path import

[julien-deramond]

Description

This PR changes the way we import resolve from path in the Vite config.
This change is suggested to be consistent with the way Vite project imports itself resolve in the vite.config.ts file in its own documentation (e.g. https://vitejs.dev/guide/build.html#multi-page-app).

It doesn't change anything in the way this example works. You can still run it locally this way:

• npm run start
• npm run build

Checklist

• If this PR is merged, I'll provide a PR in twbs/bootstrap to update the documentation accordingly. Edit: done in Docs: change vite config path import in vite guide bootstrap#39418