MM-62558 Add E2E tests for custom profile settings (#30722)

* add e2e tests for custom profile settings

* fix failed tests

* reorg folder and file convention, and add more details of the tests

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Co-authored-by: Mattermost Build <build@mattermost.com>

e2e-tests/playwright/specs/functional/channels/message_priority/standard_priority.spec.ts

@@ -28,7 +28,7 @@ test('MM-T5139: Message Priority - Standard message priority and system setting'
     await channelsPage.postMessage(testMessage);
 
     // # Verify message posts without priority label
-    const lastPost = await channelsPage.centerView.getLastPost();
+    const lastPost = await channelsPage.getLastPost();
     await lastPost.toBeVisible();
     await lastPost.toContainText(testMessage);
     await expect(lastPost.container.locator('.post-priority')).not.toBeVisible();