Update Dockerfile

Dockerfile

@@ -27,7 +27,6 @@ RUN pip install -r requirements.txt
 RUN mkdir examples && \
     cd examples && \
     for i in `seq 1 12`; do wget "https://raw.githubusercontent.com/memory-overflow/standard-ellipse-detection/master/images/test$i.jpg?raw=true"; done && \
-    image_files=("13.jpg" "27.jpg" "35.jpg" "43.jpg" "666.jpg" "666_negative.jpg" "666_positive.jpg" "different-polarity-detection_all.jpg" "im9933.jpg") && \
-    for file in "${image_files[@]}"; do wget "https://github.com/AlanLuSun/High-quality-ellipse-detection/blob/master/pics/$file?raw=true"; done
+    for file in 13.jpg 27.jpg 35.jpg 43.jpg 666.jpg 666_negative.jpg 666_positive.jpg different-polarity-detection_all.jpg im9933.jpg; do wget "https://github.com/AlanLuSun/High-quality-ellipse-detection/blob/master/pics/$file?raw=true"; done
 
 CMD ["python", "/opt/build/app.py"]