Clean up unit tests

[rosenbjerg]

Remove FluentAssertions

[Copilot]

Pull Request Overview

This PR removes the FluentAssertions dependency from the test project and replaces all FluentAssertions-style assertions with standard MSTest assertions. The changes also include relocating the TestContext property to the top of test classes for consistency.

• Removed FluentAssertions package reference from the project file
• Replaced FluentAssertions assertions (Should().Be, BeEquivalentTo, etc.) with MSTest assertions (Assert.AreEqual, CollectionAssert, etc.)
• Added try-finally blocks to properly cleanup global configuration state in tests

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

File	Description
FFMpegCore.Test/VideoTest.cs	Relocated TestContext property to the top of the class
FFMpegCore.Test/FFProbeTests.cs	Relocated TestContext property to the top of the class and reformatted a long line
FFMpegCore.Test/FFMpegCore.Test.csproj	Removed FluentAssertions package reference
FFMpegCore.Test/FFMpegArgumentProcessorTest.cs	Replaced FluentAssertions assertions with MSTest assertions and added cleanup logic for global state

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[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 69.12%. Comparing base (1c4333e) to head (012a5ca).
⚠️ Report is 36 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #578      +/-   ##
==========================================
- Coverage   71.20%   69.12%   -2.08%     
==========================================
  Files         117      117              
  Lines        2973     3343     +370     
  Branches      284      287       +3     
==========================================
+ Hits         2117     2311     +194     
- Misses        751      928     +177     
+ Partials      105      104       -1     

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