rethrow exception instead of silently return

Author: eranation

samples/spring/pet-store/src/main/java/com/amazonaws/serverless/sample/spring/StreamLambdaHandler.java

@@ -28,7 +28,7 @@ public void handleRequest(InputStream inputStream, OutputStream outputStream, Co
             } catch (ContainerInitializationException e) {
                 e.printStackTrace();
                 outputStream.close();
-                return;
+                throw new RuntimeException(e);
             }
         }