Demonstrate inconsistent WithExpectedExitCode behavior

[Jericho]

I'm submitting this PR to demonstrate the problem I tried to explain in #4013

I have written a unit test that fails due to the problem I described. In short:

• Cake script executes a command
• The command's exit code is zero
• The script is configured to expect a non-zero exit code

Given these facts, I expect Cake to throw an exception but my unit test highlights the fact that this is not happening.

[Jericho]

As I have mentioned, my unit test fails (here):

[xUnit.net 00:00:06.59]     Cake.Common.Tests.Unit.Tools.Command.CommandRunnerTests.Exception_Thrown_when_command_exit_code_is_zero_and_expected_value_is_non_zero [FAIL]
  Failed Cake.Common.Tests.Unit.Tools.Command.CommandRunnerTests.Exception_Thrown_when_command_exit_code_is_zero_and_expected_value_is_non_zero [157 ms]
  Error Message:
   Assert.IsType() Failure
Expected: Cake.Core.CakeException
Actual:   (null)
  Stack Trace:
     at Cake.Common.Tests.Unit.Tools.Command.CommandRunnerTests.Exception_Thrown_when_command_exit_code_is_zero_and_expected_value_is_non_zero() in D:\a\cake\cake\src\Cake.Common.Tests\Unit\Tools\Command\CommandRunnerTests.cs:line 230