etag is not correctly update

[dishuostec]

snowpack: 2.15.1

Steps to reproduce:

1. run npx create-snowpack-app new-dir --template @snowpack/app-template-svelte
2. enter new-dir and run npm run start
3. edit src/App.svelte, change background color for .App-header to #000000
4. reload browser

Expected:

Background color is black.

Current:

Style is missing.

Possible Sulotion:

It seems when svelte file changed, only etag for /_dist_/App.css.proxy.js?mtime=xxx was changed, but etag for origin url /_dist_/App.css.proxy.js was not update.

https://github.com/snowpackjs/snowpack/blob/626b8fa8c2109f6903ca4ea3731d4f6ae6eac00a/snowpack/src/commands/dev.ts#L1178