chore: Update test-framework to xUnit.net v3

[TheConstructor]

What does this PR do?

Currently all test-projects except Testcontainers.XunitV3.Tests use Xunit.Net v2. After this PR all test-projects except Testcontainers.Xunit.Tests use Xunit.Net v3

Why is it important?

I would expect that some day in the future Xunit.Net v2 will be discontinued. Also switching to Xunit.Net v3 means, that we can use all the new features like further Asserts and better test-cancellation. See also https://xunit.net/docs/getting-started/v3/whats-new for details

While I do think, that this should be done one day, it does not necessarily need to be today. On the other hand, I did not have problems using v3 so far (in other projects), and it will probably never be easier to switch anyway.

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[HofmeisterAn]

Indeed, if there's no major blocker, it's a good idea to switch to v3. Thanks.

[HofmeisterAn]

Thanks 🙇.

[0xced]

This pull request is a nightmare for Rider users, see RIDER-121579 - Duplication of tests. 😕

I'll try to submit a follow-up pull request to address this.

[TheConstructor]

This pull request is a nightmare for Rider users, see RIDER-121579 - Duplication of tests. 😕

I'll try to submit a follow-up pull request to address this.

Interesting. I use Rider and did not experience this while authoring the PR or in other projects. Not sure if this means it is only related to v3 > 2.0.1, but then again I use the same XUnit version at work with Rider

[0xced]

I use Rider and did not experience this while authoring the PR or in other projects.

That's interesting! Have you enabled Testing Platform support? This issue arises with xUnit.net v3 when both Testing Platform and VSTest adapters support are enabled and the test project has package references to both Microsoft.NET.Test.Sdk and xunit.runner.visualstudio. At least this is my understanding of the current situation as of JetBrains Rider 2025.1.2 and xUnit v3 2.0.2.

[TheConstructor]

I use Rider and did not experience this while authoring the PR or in other projects.

Have you enabled Testing Platform support? This issue arises with xUnit.net v3 when both Testing Platform and VSTest adapters support are enabled and the test project has package references to both Microsoft.NET.Test.Sdk and xunit.runner.visualstudio.

At least my work-Rider has "Enable Testing Platform support" disabled - maybe that's the reason it's not happening to me. I don't think I disabled it intentionally, though

[HofmeisterAn]

I don't have that problem either (tested on two different machines). "Enable Testing Platform support" is disabled too.

[HofmeisterAn]

I just refactored a test and added IXunitSerializable, and I noticed another issue. The Rider test explorer isn't showing all the test cases, one of them is missing. In my example, the test explorer shows 3 tests, but the CLI (dotnet test) runs 4 (which is correct). If I intentionally break the missing test, Rider marks the overall test red, but the specific test case still doesn't appear in the test explorer 😐.