Cleanup and muting of analyzer warnings

[jscarle]

As it currently stands, the analyzer warnings and messages make the analyzers overly difficult to follow. There are currently more that 32k messages for the entire solution:

There are also new analyzer warnings coming in .NET 9.0. Therefore to bring some order to the chaos, I started by addressing the analyzer warnings and messages that could be easily fixed. I then switched all of the analyzer warnings from suggestion to silent for all test projects. I then set the remaining analyzer warnings in the main project to none.

In the future, I'll look into standardizing all of the analyzer configurations and merge everything down to two .editorconfigs files, one for the main project, and another for all of the tests, while also addressing as many warning as is logical.

[jscarle]

@Rob-Hague FYI.

[Rob-Hague]

Thanks for tackling some of the noise. On initial look, I think test classes are supposed to be public? I can see that they are not running in CI

[jscarle]

@WojciechNagorski@Rob-Hague Ready for review and merge.

[Rob-Hague]

Something is wrong with CI...

It crashed on the latest commit on this PR: https://ci.appveyor.com/project/drieseng/ssh-net/builds/49517362/job/8rdxcr7v12990kdx?fullLog=true

On some builds it is only running 840 tests on Ubuntu: https://ci.appveyor.com/project/drieseng/ssh-net/builds/49516084https://ci.appveyor.com/project/drieseng/ssh-net/builds/49513131

[jscarle]

@Rob-Hague All tests seem to be passing now. I also cleaned up the diff by removing any formatting changes to make it easier to review.

[Rob-Hague]

Thanks. CI managed to finish all 2951 tests on Ubuntu, so this is good to merge from me.