Add IgnoreExitCode to ToolSettings

- When true, then ProcessExitCode method is not called

src/Cake.Core.Tests/Unit/Tooling/ToolTests.cs

@@ -144,6 +144,21 @@ public void Should_Throw_On_Invalid_ExitCode_Validated_By_Custom_Validator()
                 // Then
                 AssertEx.IsCakeException(result, "UnitTest");
             }
+
+            [Fact]
+            public void Should_Not_Throw_On_Invalid_ExitCode_When_IgnoreExitCode_Is_True()
+            {
+                // Given
+                var fixture = new DummyToolFixture();
+                fixture.Settings.IgnoreExitCode = true;
+                fixture.GivenProcessExitsWithCode(10);
+
+                // When
+                var result = fixture.Run();
+
+                // Then
+                Assert.IsNotType<Exception>(result);
+            }
         }
     }
 }

src/Cake.Core/Tooling/Tool.cs

@@ -117,7 +117,10 @@ protected void Run(
             // Post action specified?
             postAction?.Invoke(process);
 
-            ProcessExitCode(process.GetExitCode());
+            if (!settings.IgnoreExitCode)
+            {
+                ProcessExitCode(process.GetExitCode());
+            }
         }
 
         /// <summary>

src/Cake.Core/Tooling/ToolSettings.cs

@@ -73,5 +73,17 @@ public class ToolSettings
         /// </code>
         /// </example>
         public IDictionary<string, string> EnvironmentVariables { get; set; } = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);
+
+        /// <summary>
+        /// Gets or sets a value indicating whether the exit code from the tool process causes an exception to be thrown.
+        /// </summary>
+        /// <example>
+        /// <code>
+        /// DotNetCoreTest("MyProject.csproj", new DotNetCoreTestSettings {
+        ///     IgnoreExitCode = true
+        /// });
+        /// </code>
+        /// </example>
+        public bool IgnoreExitCode { get; set; }
     }
 }