Fix assets path issue for "compound-design-tokens" package

Fixed path issue for "compound-design-tokens" package independent of whether the package is cloned and linked within "matrix-react-sdk" or not.

Resource paths are e.g. ...

- Not linked package -
resourcePath: C:\src\matrix-react-sdk\node_modules\@vector-im\compound-design-tokens\icons\chat-solid.svg

- Cloned & linked package -
resourcePath: C:\src\compound-design-tokens\icons\chat-solid.svg

Problem: 
The "compound-design-tokens" package does not have a 'dist' or "res" subfolder for the assets so that the regex /^.*[/\\](dist|res)[/\\]/ does not match. 

Solution: 
Add the missing root folder name for the compound tokens assets to the regex in the "webpack.config.js" to match the paths, with resulting regex... 

/^.*[/\\](dist|res|compound-design-tokens)[/\\]/

Tested both scenarios (linked/not linked) on Windows.

webpack.config.js

@@ -807,7 +807,7 @@ function getAssetOutputPath(url, resourcePath) {
     const isKaTeX = resourcePath.includes("KaTeX");
     // `res` is the parent dir for our own assets in various layers
     // `dist` is the parent dir for KaTeX assets
-    const prefix = /^.*[/\\](dist|res)[/\\]/;
+    const prefix = /^.*[/\\](dist|res|compound-design-tokens)[/\\]/;
 
     /**
      * Only needed for https://github.com/vector-im/element-web/pull/15939
@@ -819,20 +819,6 @@ function getAssetOutputPath(url, resourcePath) {
     }
     let outputDir = path.dirname(resourcePath).replace(prefix, "");
 
-    /**
-     * Imports from Compound are "absolute", we need to strip out the prefix
-     * coming before the npm package name.
-     *
-     * This logic is scoped to compound packages for now as they are the only
-     * package that imports external assets. This might need to be made more
-     * generic in the future
-     */
-    const compoundImportsPrefix = /@vector-im(?:\\|\/)compound-(.*?)(?:\\|\/)/;
-    const compoundMatch = outputDir.match(compoundImportsPrefix);
-    if (compoundMatch) {
-        outputDir = outputDir.substring(compoundMatch.index + compoundMatch[0].length);
-    }
-
     if (isKaTeX) {
         // Add a clearly named directory segment, rather than leaving the KaTeX
         // assets loose in each asset type directory.