Fix flaky assertion in OverlappingExtensions_AllMatchTypes_Comprehensive

[Copilot]

MatchTypesTests.OverlappingExtensions_AllMatchTypes_Comprehensive asserted that no bar* result contained the substring "foo" — but checked the full absolute path. GetTestFilePath() appends random characters, so whenever those characters happened to spell foo (e.g. /tmp/#MatchTypesTests_Directory_GetFiles_foopzs3q...), every result matched and the test failed. Not a product regression.

Changes

• Replaced the count check plus substring filter with an exact expected-path comparison of the four bar* matches, which is strictly stronger (verifies identity, not just count) and independent of the random directory name.

-Assert.Equal(4, win32Paths.Length); // bar, bar.b, bar.ba, bar.baz
-Assert.DoesNotContain(win32Paths, p => p.Contains("foo"));
+FSAssert.EqualWhenOrdered(new string[] {
+    Path.Combine(testDirectory.FullName, "bar"),
+    Path.Combine(testDirectory.FullName, "bar.b"),
+    Path.Combine(testDirectory.FullName, "bar.ba"),
+    Path.Combine(testDirectory.FullName, "bar.baz")
+}, win32Paths);

Also scanned for other places where this could happen in the test file.

• Fixes OverlappingExtensions_AllMatchTypes_Comprehensive failing on Assert.DoesNotContain #128907

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[Copilot]

🟢 Approval recommended

The deterministic exact-path assertions address the flaky test without product changes.

Pull request overview

This test-only PR fixes a flaky filesystem enumeration assertion by using deterministic exact-path comparisons.

Changes:

• Verifies all expected bar* results exactly.
• Strengthens path matching assertions.

File summaries

File	Description
src/libraries/System.Runtime/tests/System.IO.FileSystem.Tests/Enumeration/MatchTypesTests.cs	Makes path assertions deterministic and precise.

Review details

• Files reviewed: 1/1 changed files
• Comments generated: 0
• Review effort level: Lite

[adamsitnik]

LGTM, thank you for fixing the flaky test and closing one of very few remaining .NET 11 issues @jozkee