Rollup 3 switched the way sourcemaps were handled to be more consistent between the in-memory representation and what ultimately gets emitted to disk. Part of this change was moving the sourcemaps themselves to be assets within the bundle.

At the same time, vite's `generateBundle` hook for the `assetPlugin` is configured to delete assets within the bundle (with the exception of "ssr-manifest.json"). Since `.js.map` files are now considered assets within the bundle at this stage, vite is removing the sourcemaps from the bundle when `build.ssr = true` and they never wind up on disk.

This change adds an additional check to see if the file ends with `.js.map`, `.cjs.map`, or `.mjs.map` and it will leave these files in the bundle so that they are emitted to the outDir when the bundle is written.