add en

doc/doc_en/PP-OCRv3_introduction_en.md

@@ -56,6 +56,7 @@ The ablation experiments are as follows:
 |ID|Strategy|Model Size|Hmean|The Inference Time（cpu + mkldnn)|
 |-|-|-|-|-|
 |baseline teacher|PP-OCR server|49M|83.2%|171ms|
+|baseline teacher|DB-R50|99M|83.5%|260ms|
 |teacher1|DB-R50-LK-PAN|124M|85.0%|396ms|
 |teacher2|DB-R50-LK-PAN-DML|124M|86.0%|396ms|
 |baseline student|PP-OCRv2|3M|83.2%|117ms|