Table: Remove hardcoded assumption of __nestedFrames field name (#115117)

* Table: Remove hardcoded assumption of __nestedFrames field name

* E2E for nested tables

* Apply suggestion from @fastfrwrd

e2e-playwright/panels-suite/table-kitchenSink.spec.ts

@@ -343,6 +343,33 @@ test.describe('Panels test: Table - Kitchen Sink', { tag: ['@panels', '@table']
     // TODO -- saving for another day.
   });
 
+  test('Tests nested table expansion', async ({ gotoDashboardPage, selectors, page }) => {
+    const dashboardPage = await gotoDashboardPage({
+      uid: DASHBOARD_UID,
+      queryParams: new URLSearchParams({ editPanel: '4' }),
+    });
+
+    await expect(
+      dashboardPage.getByGrafanaSelector(selectors.components.Panels.Panel.title('Nested tables'))
+    ).toBeVisible();
+
+    await waitForTableLoad(page);
+
+    await expect(page.locator('[role="row"]')).toHaveCount(3); // header + 2 rows
+
+    const firstRowExpander = dashboardPage
+      .getByGrafanaSelector(selectors.components.Panels.Visualization.TableNG.RowExpander)
+      .first();
+
+    await firstRowExpander.click();
+    await expect(page.locator('[role="row"]')).not.toHaveCount(3); // more rows are present now, it is dynamic tho.
+
+    // TODO: test sorting
+
+    await firstRowExpander.click();
+    await expect(page.locator('[role="row"]')).toHaveCount(3); // back to original state
+  });
+
   test('Tests tooltip interactions', async ({ gotoDashboardPage, selectors }) => {
     const dashboardPage = await gotoDashboardPage({
       uid: DASHBOARD_UID,