GH-160 - Polishing.

Moved the message population for the failure analyzer to the exception to be able to give more actionable feedback and educated users on the cause of the problem.

spring-modulith-runtime/src/test/java/org/springframework/modulith/runtime/autoconfigure/SpringModulithRuntimeAutoConfigurationIntegrationTests.java

@@ -54,7 +54,7 @@ class SpringModulithRuntimeAutoConfigurationIntegrationTests {
 				});
 	}
 
-	@Test
+	@Test // GH-160
 	void missingArchUnitRuntimeDependencyEscalatesOnContextStartup() {
 
 		new ApplicationContextRunner()
@@ -65,8 +65,8 @@ class SpringModulithRuntimeAutoConfigurationIntegrationTests {
 
 					assertThat(context).hasFailed();
 					assertThat(context.getStartupFailure().getCause())
-						.isInstanceOf(BeanInstantiationException.class)
-						.cause().isInstanceOf(MissingRuntimeDependencyException.class);
+							.isInstanceOf(BeanInstantiationException.class)
+							.cause().isInstanceOf(MissingRuntimeDependency.class);
 
 					context.close();
 				});