update swin export config (#4418)

configs/faster_rcnn/_base_/faster_rcnn_swin_reader.yml

@@ -30,10 +30,10 @@ EvalReader:
 
 TestReader:
   inputs_def:
-    image_shape: [1, 3, 800, 1344]
+    image_shape: [1, 3, 640, 640]
   sample_transforms:
   - Decode: {}
-  - Resize: {interp: 2, target_size: [800, 1344], keep_ratio: True}
+  - Resize: {interp: 2, target_size: [640, 640], keep_ratio: False}
   - NormalizeImage: {is_scale: true, mean: [0.485,0.456,0.406], std: [0.229, 0.224,0.225]}
   - Permute: {}
   batch_transforms: