I believe I forgot a .finish call which is needed for proper cleanup and was causing failed tests

Author: benrosen78

Tests/AWSLambdaRuntimeTests/LambdaRuntimeClientTests.swift

@@ -386,6 +386,7 @@ struct LambdaRuntimeClientTests {
                 let (_, writer) = try await runtimeClient.nextInvocation()
                 let error = MyCustomError(message: "Something went wrong")
                 try await writer.reportError(error)
+                try await writer.finish()
             }
         }
 
@@ -401,6 +402,7 @@ struct LambdaRuntimeClientTests {
                 let (_, writer) = try await runtimeClient.nextInvocation()
                 let error = MyEnumError.anotherCase("test")
                 try await writer.reportError(error)
+                try await writer.finish()
             }
         }
     }