Update Dockerfile

Dockerfile

@@ -15,7 +15,7 @@ RUN pip install --no-cache-dir --upgrade -r requirements.txt
 RUN pip install torch torchvision --index-url https://download.pytorch.org/whl/cpu
 RUN pip install torchxrayvision
 RUN pip install grad-cam
-RUN pip install opencv-python
+RUN pip install opencv-python-headless
 RUN pip install transformers
 
 COPY --chown=user . /app