(fix) Throttle restarting the language server

If another restart happens while a restart is already in progress, VS Code trips up and shows error messages

Author: dummdidumm

packages/svelte-vscode/src/extension.ts

@@ -143,14 +143,21 @@ export function activate(context: ExtensionContext) {
         })
     );
 
+    let restartingLs = false;
     async function restartLS(showNotification: boolean) {
+        if (restartingLs) {
+            return;
+        }
+
+        restartingLs = true;
         await ls.stop();
         ls = createLanguageServer(serverOptions, clientOptions);
         context.subscriptions.push(ls.start());
         await ls.onReady();
         if (showNotification) {
             window.showInformationMessage('Svelte language server restarted.');
         }
+        restartingLs = false;
     }
 
     function getLS() {