Implement fallback for automated test/coverage detection

[costin-zaharia-sonarsource]

Currently, automatic test/coverage detection works only on machines that have the enterprise version of Visual Studio installed and it would be great to have a fallback and when the tool is missing, automatically download it from NuGet.org.

This will probably increase the build time due to the download so we might want to provide a way to enable/disable this feature.

With enterprise version installed:

Calling the TFS Processor executable...
Attempting to locate the CodeCoverage.exe tool...
Attempting to locate the CodeCoverage.exe tool using setup configuration...
Code coverage command line tool: C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\Team Tools\Dynamic Code Coverage Tools\CodeCoverage.exe

without:

Calling the TFS Processor executable...
Attempting to locate the CodeCoverage.exe tool...
Attempting to locate the CodeCoverage.exe tool using setup configuration...
Attempting to locate the CodeCoverage.exe tool using registry...
WARNING: Failed to find the code coverage command line tool. Possible cause: Visual Studio is not installed, or the installed version does not support code coverage.