remove redundant sourcemap flags

[nichtsam]

Test Plan

Checklist

• [ ] Tests updated
• [ ] Docs updated

Screenshots

[kiliman]

I'm pretty sure you need those flags to get sourcemaps on a production build. I'm not sure what is meant by "redundant".

[nichtsam]

I'm not sure how to verify this, here are what I checked:

I built

• with flags and without build.sourcemap = true => generates sourcemap
• without flags and with build.sourcemap = true => generates sourcemap
• withboth => generates sourcemap
• without both => no sourcemap

I went to check the source code of remix vite:build, and I believe what the flags do is setting build.sourcemap = true for their own environment, which is the same as setting it in vite.config.ts. https://github.com/remix-run/remix/blob/main/packages/remix-dev/vite/build.ts#L229

In addition, my own project only have build.sourcemap = true and doesn't have flags, it's working.

[kentcdodds]

Thanks!