minor symfony#2383 [Svelte][Docs] Fix a broken link (MrYamous)

This PR was merged into the 2.x branch.

Discussion
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[Svelte][Docs] Fix a broken link

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| Issues        | Fix symfony#2381
| License       | MIT

Fix a broken link
The file has been moved/renamed in symfony#2268 and symfony#2284

Commits
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a16d51d [Svelte][Docs] Fix a broken link

Author: Kocal

src/Svelte/doc/index.rst

@@ -121,7 +121,7 @@ AssetMapper requires some extra steps.
 
 #. Compile your ``.svelte`` files to pure JavaScript files. This can be done by
    using the ``svelte/compiler`` library, but is a bit of a non-standard process.
-   For an example, see https://github.com/symfony/ux/blob/2.x/ux.symfony.com/bin/compile_svelte.js.
+   For an example, see https://github.com/symfony/ux/blob/2.x/ux.symfony.com/assets/svelte/build/build.js.
 
 #. Point this library at the "built" controllers directory that contains the final
    JavaScript files: