GH2470: call multiple tasks from cli and pass them to run target

[FrankRay78]

This PR fully implements #2470, 'Call multiple tasks from CLI and pass them to RunTarget'

Significant unit test coverage has been added for the changes, including minor refactoring and improvements to the existing codebase when encountered.

Significant effort was undertaken to ensure the changes introduced in this PR maintained backward compatibility.

Given the following cake build script,

var targets = Arguments<string>("target", "A");

Task("A");

Task("B");

Task("C");

RunTargets(targets);

This PR extends Cake to operate as follows:

[devlead]

@FrankRay78 your changes have been merged, thanks for your contribution 👍

[juwens]

@devlead and @FrankRay78 is this supposed to work with frosting?

when i do build.ps1 --target=A --target=B only B gets executed.

[punker76]

@devlead and @FrankRay78 is this supposed to work with frosting?

when i do build.ps1 --target=A --target=B only B gets executed.

@juwens You must use RunTargets instead RunTarget in your cake script

RunTargets(Arguments<string>("target", new []{ "Default" }))

Then you can run multiple targets

dotnet-cake.exe build.cake --target=target1 --target=target2