fix: Add python-is-python3 package and upgrade pip in GPU base image

Author: kshitijrajsharma

Dockerfile.pb

@@ -23,7 +23,7 @@ FROM nvidia/cuda:${CUDA_TAG} AS gpu-base
 ENV DEBIAN_FRONTEND=noninteractive
 RUN apt-get update && \
     apt-get install -y --no-install-recommends \
-    python3 python3-pip build-essential gcc g++ python3-dev python3-rtree \
+    python3 python3-pip build-essential gcc g++ python3-dev python3-rtree python-is-python3 \
     gdal-bin libgdal-dev python3-gdal python3-opencv libspatialindex-dev \
     && rm -rf /var/lib/apt/lists/* && \
     python3 -m pip install --upgrade pip