[test-quarantine] Quarantine VirtualizationTest E2E tests (spacer height flakiness)

[github-actions]

Quarantines 2 E2E Virtualization test methods that intermittently fail with assertion errors on CSS spacer height values.

Failing Tests

• VirtualizationTest.CanRenderHtmlTable (also runs as ServerVirtualizationTest.CanRenderHtmlTable)
• VirtualizationTest.CanElevateEffectiveMaxItemCount_WhenOverscanExceedsMax (also runs as ServerVirtualizationTest.CanElevateEffectiveMaxItemCount_WhenOverscanExceedsMax)

Error

Assert.Contains() Failure: Sub-string not found
String:   "height: 30px; flex-shrink: 0; display: ..."
Not found: "height: 0px; flex-shrink: 0;"

Changes

• VirtualizationTest.cs: Added using Microsoft.AspNetCore.InternalTesting; and [QuarantinedTest] to 2 methods

Fixes #65853

Generated by Daily Test Quarantine Management · ◷