test(playwright): additional dataset list playwright tests (#36684)

Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

superset-frontend/playwright/components/modals/DuplicateDatasetModal.ts

@@ -55,7 +55,10 @@ export class DuplicateDatasetModal extends Modal {
     datasetName: string,
     options?: { timeout?: number; force?: boolean },
   ): Promise<void> {
-    await this.nameInput.fill(datasetName, options);
+    const input = this.nameInput.element;
+    // Clear existing text then fill (fill() clears first, but explicit clear is more reliable)
+    await input.clear();
+    await input.fill(datasetName, options);
   }
 
   /**