rm repeated

doc/doc_en/update_en.md

@@ -15,8 +15,6 @@
 - 2020.6.8 Add [datasets](./datasets_en.md) and keep updating
 - 2020.6.5 Support exporting `attention` model to `inference_model`
 - 2020.6.5 Support separate prediction and recognition, output result score
-- 2020.6.5 Support exporting `attention` model to `inference_model`
-- 2020.6.5 Support separate prediction and recognition, output result score
 - 2020.5.30 Provide Lightweight Chinese OCR online experience
 - 2020.5.30 Model prediction and training support on Windows system
 - 2020.5.30 Open source general Chinese OCR model