Update dependency: xUnit

[DennisDyallo]

Description

Updating xUnit https://xunit.net/releases/v2/2.8.1

Fixes # <link to issue(s)>

Type of change

Please delete options that are not relevant.

• [x] Dependency update
• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [ ] This change requires a documentation update

How has this been tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration

Checklist:

• [ ] My code follows the style guidelines of this project
• [ ] I have performed a self-review of my own code
• [ ] I have run dotnet format to format my code
• [ ] I have commented my code, particularly in hard-to-understand areas
• [ ] I have made corresponding changes to the documentation
• [ ] My changes generate no new warnings
• [ ] I have added tests that prove my fix is effective or that my feature works
• [x] New and existing unit tests pass locally with my changes

[github-actions[bot]]

Test Results: Windows

    2 files      2 suites   4s :stopwatch: 3 700 tests 3 700 :white_check_mark: 0 :zzz: 0 :x: 3 702 runs  3 702 :white_check_mark: 0 :zzz: 0 :x:

Results for commit c155fa29.

[github-actions[bot]]

Test Results: Ubuntu

    2 files      2 suites   9s :stopwatch: 3 692 tests 3 692 :white_check_mark: 0 :zzz: 0 :x: 3 694 runs  3 694 :white_check_mark: 0 :zzz: 0 :x:

Results for commit c155fa29.

[github-actions[bot]]

Test Results: MacOS

    2 files      2 suites   3s :stopwatch: 3 692 tests 3 692 :white_check_mark: 0 :zzz: 0 :x: 3 694 runs  3 694 :white_check_mark: 0 :zzz: 0 :x:

Results for commit c155fa29.

[github-actions[bot]]

Package	Line Rate	Branch Rate	Complexity	Health
Yubico.Core	42%	31%	4257	➖
Yubico.YubiKey	51%	47%	18825	➖
Summary	49% (31966 / 65160)	45% (8176 / 18318)	23082	➖

Minimum allowed line rate is 40%