Use the instance ExecuteAsync method.

msbuild/Xamarin.MacDev.Tasks/Tasks/CreateInstallerPackage.cs

@@ -81,7 +81,7 @@ public override bool Execute ()
 			var args = GenerateCommandLineCommands ();
 			var executable = GetExecutable (args, "productbuild", ProductBuildPath);
 			cancellationTokenSource = new CancellationTokenSource ();
-			ExecuteAsync (Log, executable, args, workingDirectory: OutputDirectory, cancellationToken: cancellationTokenSource.Token).Wait ();
+			ExecuteAsync (executable, args, workingDirectory: OutputDirectory, cancellationToken: cancellationTokenSource.Token).Wait ();
 			return !Log.HasLoggedErrors;
 		}
 

msbuild/Xamarin.MacDev.Tasks/Tasks/XamarinTask.cs

@@ -109,9 +109,9 @@ protected string GetSdkPlatform (bool isSimulator)
 			return PlatformFrameworkHelper.GetSdkPlatform (Platform, isSimulator);
 		}
 
-		protected System.Threading.Tasks.Task<Execution> ExecuteAsync (string fileName, IList<string> arguments, Dictionary<string, string?>? environment = null, bool mergeOutput = true, bool showErrorIfFailure = true, string? workingDirectory = null)
+		protected System.Threading.Tasks.Task<Execution> ExecuteAsync (string fileName, IList<string> arguments, Dictionary<string, string?>? environment = null, bool mergeOutput = true, bool showErrorIfFailure = true, string? workingDirectory = null, CancellationToken? cancellationToken = null)
 		{
-			return ExecuteAsync (Log, fileName, arguments, SdkDevPath, environment, mergeOutput, showErrorIfFailure, workingDirectory);
+			return ExecuteAsync (Log, fileName, arguments, SdkDevPath, environment, mergeOutput, showErrorIfFailure, workingDirectory, cancellationToken);
 		}
 
 		static int executionCounter;