Fix ConfigurationFileProvider file lock and GitCheckoutInformation type check

ConfigurationFileProvider: use a unique subdirectory per instance under
ApplicationData/config-runtime/{guid} to avoid Windows file-locking
collisions when multiple tests run in parallel writing the same
versions.yml/products.yml files. Original CreateTempSubdirectory gave
unique dirs; the fixed path broke parallel test isolation on Windows.

GitCheckoutInformation.Create: the guard `fileSystem is not FileSystem`
returned hardcoded test data for any ScopedFileSystem, including RealRead
wrapping a real FileSystem. RealRead is used in GitCheckoutInformationTests
which expects real git metadata. Change to check the type name for "Mock"
so only MockFileSystem-backed instances return test data.

Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>

Author: Mpdreamz

src/Elastic.Documentation.Configuration/ConfigurationFileProvider.cs

@@ -45,10 +45,11 @@ public ConfigurationFileProvider(
 		_fileSystem = fileSystem;
 		_assemblyName = typeof(ConfigurationFileProvider).Assembly.GetName().Name!;
 		SkipPrivateRepositories = skipPrivateRepositories;
-		var configRuntimeDir = Path.Join(Paths.ApplicationData.FullName, "config-runtime");
+		// Use a unique subdirectory per instance to avoid file-locking collisions when
+		// multiple processes or parallel tests share the same ApplicationData path.
+		var configRuntimeDir = Path.Join(Paths.ApplicationData.FullName, "config-runtime", Guid.NewGuid().ToString("N"));
 		TemporaryDirectory = fileSystem.DirectoryInfo.New(configRuntimeDir);
-		if (!TemporaryDirectory.Exists)
-			TemporaryDirectory.Create();
+		TemporaryDirectory.Create();
 
 		// TODO: This doesn't work as expected if a github actions consumer repo has a `config` directory.
 		// ConfigurationSource = configurationSource ?? (

src/Elastic.Documentation/GitCheckoutInformation.cs

@@ -45,7 +45,9 @@ public static GitCheckoutInformation Create(IDirectoryInfo? source, IFileSystem
 		if (source is null)
 			return Unavailable;
 
-		if (fileSystem is not FileSystem)
+		// Return test data for in-memory (mock) file systems. ScopedFileSystem wraps the real
+		// FileSystem so we check if the FS implementation name indicates an in-memory mock.
+		if (fileSystem.GetType().Name.Contains("Mock", StringComparison.OrdinalIgnoreCase))
 		{
 			return new GitCheckoutInformation
 			{