updated requirements.txt filename in docker

Business_cards/Dockerfile

 COPY . .
 
 # Install any needed packages specified in requirements.txt
-RUN pip install --no-cache-dir -r requirement.txt
+RUN apt update && apt install -y libgl1-mesa-glx && apt --fix-broken install && \
+    pip install --no-cache-dir -r requirement.txt
 
 # Make port 80 available to the world outside this container
 EXPOSE 1112