Upgrade `Nuget.Client` from `6.11.1.2` to `6.12.0.127`

[JamieMagee]

What are you trying to accomplish?

References:

• https://github.com/NuGet/NuGet.Client/compare/6.11.1.2...6.12.0.127
• https://learn.microsoft.com/en-us/nuget/release-notes/nuget-6.12

Anything you want to highlight for special attention from reviewers?

How will you know you've accomplished your goal?

Checklist

• [x] I have run the complete test suite to ensure all tests and linters pass.
• [x] I have thoroughly tested my code changes to ensure they work as expected, including adding additional tests for new functionality.
• [x] I have written clear and descriptive commit messages.
• [x] I have provided a detailed description of the changes in the pull request, including the problem it addresses, how it fixes the problem, and any relevant details about the implementation.
• [x] I have ensured that the code is well-documented and easy to understand.