Update Dockerfile to include python3-pip

Added python3-pip to the list of packages in the Dockerfile to ensure that pip is available in the container environment. This is needed to manage Python package installations effectively within the Docker container and to support the subsequent pip installations of other dependencies.

#12345

Dockerfile

@@ -57,7 +57,7 @@ WORKDIR /app/backend
 COPY ./backend/requirements.txt ./requirements.txt
 
 RUN apt-get update && \
-    apt-get install -y --no-install-recommends python3.11 ffmpeg libsm6 libxext6 pandoc netcat-openbsd && \
+    apt-get install -y --no-install-recommends python3.11 python3-pip ffmpeg libsm6 libxext6 pandoc netcat-openbsd && \
     rm -rf /var/lib/apt/lists/*
 
 RUN pip3 install torch torchvision torchaudio --no-cache-dir