feat(TreeView): publish single select tree (#11938)

* feat(TreeView): publish single select tree

* chore: update snapshots

* docs(treeview): update stories and controls, remove v11 feature flag

* chore: update snapshots

* docs(TreeView): touch TreeView.mdx

* fix(TreeView): update caret alignment
partially addresses #11858

* Update e2e/components/TreeView/TreeView-test.e2e.js

* Update e2e/components/TreeView/TreeView-test.e2e.js

* fix(treeview): update node icon position

Co-authored-by: Taylor Jones <taylor.jones826@gmail.com>
Co-authored-by: Taylor Jones <tay1orjones@users.noreply.github.com>

e2e/components/TreeView/TreeView-test.e2e.js

@@ -0,0 +1,37 @@
+/**
+ * Copyright IBM Corp. 2016, 2018
+ *
+ * This source code is licensed under the Apache-2.0 license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+'use strict';
+
+const { expect, test } = require('@playwright/test');
+const { themes } = require('../../test-utils/env');
+const { snapshotStory, visitStory } = require('../../test-utils/storybook');
+
+test.describe('TreeView', () => {
+  themes.forEach((theme) => {
+    test.describe(theme, () => {
+      test('treeview @vrt', async ({ page }) => {
+        await snapshotStory(page, {
+          component: 'TreeView',
+          id: 'components-treeview--default',
+          theme,
+        });
+      });
+    });
+  });
+
+  test('accessibility-checker @avt', async ({ page }) => {
+    await visitStory(page, {
+      component: 'TreeView',
+      id: 'components-treeview--default',
+      globals: {
+        theme: 'white',
+      },
+    });
+    await expect(page).toHaveNoACViolations('TreeView');
+  });
+});