OSOE-49: Replace Windows-only code in UI Testing Toolbox, upgrade to latest Atata/Selenium

[sarahelsaig]

OSOE-49

Fixes #123.

Release Notes

• Please add these new lines to your .gitattributes, because we get IDE0055 warnings when the C# source file has Unix style line endings. Some .cs files will be affected, please run git add --renormalize . on your projects and git submodule foreach git add --renormalize . if they include submodules.
• The setup and configuration for using SQL Server from a Docker container has changed. See new instructions here. You can also find a sample config and setup steps in the .github directory.
• We have upgraded to Atata 2 which in turn upgraded to Selenium 4. Both introduce breaking changes, although most of it is pretty easy to fix. Replace every RemoteWebDriver with IWebDriver and if you execute scripts or take screenshots then use the extension methods (here, here and here).
• If you have several UI test projects it can be cumbersome to maintain a TestConfiguration.json file for each. Instead, you can set the value of the LOMBIQ_UI_TESTING_TOOLBOX_SHARED_TEST_CONFIGURATION environment variable to the absolute path of a central configuration file and then each project will look it up. If you place an individual TestConfiguration.json into a test directory it will still take precedence in case you need special configuration for just that one.
• New HelpfulLibraries.Cli project has been added, please use and expand it for all your Process and CliWrap needs.

[sarahelsaig]

I have "resolved" the comments regarding the changes you made. I think it would've made more sense to include those as comments in your own PR.