refactor: improve mocking tests in FileSystemTests

[vbreuss]

Refactors FileSystemTests to more directly validate mocked IFile behavior, and updates test dependencies to support the new assertion/verification style.

Changes:

• Update Mock_File_Succeeds to assert ReadAllText returns a configured value and verify the call occurred.
• Add aweXpect.Mockolate to the shared test package references.
• Bump Mockolate package version and centrally define the aweXpect.Mockolate version.

[Copilot]

Pull request overview

Refactors FileSystemTests to more directly validate mocked IFile behavior, and updates test dependencies to support the new assertion/verification style.

Changes:

• Update Mock_File_Succeeds to assert ReadAllText returns a configured value and verify the call occurred.
• Add aweXpect.Mockolate to the shared test package references.
• Bump Mockolate package version and centrally define the aweXpect.Mockolate version.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
tests/TestableIO.System.IO.Abstractions.Wrappers.Tests/FileSystemTests.cs	Strengthens the mock test by asserting return value and verifying invocation.
tests/Directory.Build.props	Adds aweXpect.Mockolate to the common test dependencies.
Directory.Packages.props	Updates central package versions for Mockolate and adds aweXpect.Mockolate.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[github-actions]

This is addressed in release v22.1.1.