Add e2e tests

[dfederm]

No description provided.

[jeffkl]

Do you want to fix the CI to install .NET and run dotnet test? I see this in the output at the moment:

Unable to load types from the test source 'D:\a\PackagesConfigConverter\PackagesConfigConverter\src\PackagesConfigConverter.UnitTests\obj\Debug\net472\PackagesConfigConverter.UnitTests.dll'. Some or all of the tests in this source may not be discovered. If you are running unit tests for Windows Store apps and referencing custom WinMD type then please visit http://go.microsoft.com/fwlink/?LinkId=238340 for more info. Error details: System.IO.FileNotFoundException: Could not load file or assembly 'PackagesConfigConverter, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null' or one of its dependencies. The system cannot find the file specified.
System.IO.FileNotFoundException: Could not load file or assembly 'log4net, Version=2.0.17.0, Culture=neutral, PublicKeyToken=669e0ddf0bb1aa2a' or one of its dependencies. The system cannot find the file specified.
.

https://github.com/jeffkl/PackagesConfigConverter/actions/runs/10291694138/job/28484538534

[dfederm]

Looks like all the tests ran though (4 of 4), so next change?