Add an option to disable the detection of a CI/CD environment to over…

…ride the disabling of output coloring

Add significant performance improvements

* Remove lock statement from environment variables unit tests

* Add inline data with different text casing to environment variables unit tests
* Code cleanup
* Unify line endings
* Bump test packages

Add support for ConsoleColor arguments

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Target .NET 6

* Improve regex performance

* Test code cleanup
* Multi-target .NET Standard 2.0 / .NET 5

Target .NET 5.0

Bump version

Update build info