[Build] Assembly processor issues should dump exception to editor build modal

Release Type: Github, latest

Describe the bug
When the assembly processor is invoked from the editor building the project, be it when the project is opened, reloaded or played, exceptions generated within the assembly processor are not caught by the modal, just a generic issue specifying that it couldn't build the project.

To Reproduce
Steps to reproduce the behavior:

1. Append the following to one of the components source added to a scene to trigger a serialization exception within the AssemblyProcessor:

public System.Collections.Generic.List<TestSerializationClass> ListTest = new System.Collections.Generic.List<TestSerializationClass>();
public TestSerializationClass TestObject = new TestSerializationClass();
public class TestSerializationClass
{
    public float testField;
}

2. Build and run the project, the modal should show an error but not the exact exception

You should be able to see the actual exception within the output window of your IDE when running the project itself.

Expected behavior
Exception inside of the modal

Screenshots
The kind of obtuse issue this outputs:

When it should output the exception itself to help the user debug

Start with the AssemblyProcessor invocation used when building from the editor, then trace how its exceptions reach the editor build modal. Reproduce the serialization exception with the provided component code and compare the modal output with the IDE output window; done when the modal displays the actual exception instead of only the generic build failure.