Update Svelte Language Server PnP Configuration (#5953)

**What's the problem this PR addresses?**
My PR sveltejs/language-tools#2196 introduces
a small change alongside a new setting that allows
sveltejs-language-tools to resolve PnP in ESM files, most importantly in
a `svelte.config.js`. Please note that this PR shouldn't go in until
that PR is ready as otherwise the Svelte language server itself will not
have the setting available.

Also I'm no expert in Yarn PnP so if this is the wrong implementation
avenue I would welcome advice!

**How did you fix it?**
The main portion of the solution is in the linked PR. The addition here
is to set `svelte.language-server.runtime-args` to `["--loader",
"./.pnp.loader.mjs"]`.

**Checklist**
- [x] I have read the [Contributing
Guide](https://yarnpkg.com/advanced/contributing).
- [x] I have set the packages that need to be released for my changes to
be effective.
- [x] I will check that all automated PR checks pass before the PR gets
reviewed.

Author: DavidArchibald

.yarn/versions/ddf3a56f.yml

@@ -0,0 +1,2 @@
+releases:
+  "@yarnpkg/sdks": minor

packages/yarnpkg-sdks/sources/sdks/vscode.ts

@@ -113,6 +113,7 @@ export const generateSvelteLanguageServerWrapper: GenerateIntegrationWrapper = a
         `bin/server.js` as PortablePath,
       ),
     ),
+    [`svelte.language-server.runtime-args`]: [`--loader`, `./.pnp.loader.mjs`],
   });
 
   await addVSCodeWorkspaceConfiguration(pnpApi, VSCodeConfiguration.extensions, {