fixed pip version (RVC-Project#2238)

Author: keitarou

Dockerfile

@@ -28,6 +28,7 @@ RUN apt-get update && \
 # Set Python 3.9 as the default
 RUN update-alternatives --install /usr/bin/python python /usr/bin/python3.9 1
 
+RUN python3 -m pip install --upgrade pip==24.0
 RUN python3 -m pip install --no-cache-dir -r requirements.txt
 
 RUN aria2c --console-log-level=error -c -x 16 -s 16 -k 1M https://huggingface.co/lj1995/VoiceConversionWebUI/resolve/main/pretrained_v2/D40k.pth -d assets/pretrained_v2/ -o D40k.pth