fix: CI containers install nvidia-cudnn-cu12 vs. nvidia-cudnn-cu13 based on CUDA Version (#1742)

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## 📌 Description

Current `flashinfer-ci-cu[12x, 130]` containers all install
[nvidia-cudnn-cu12](https://pypi.org/project/nvidia-cudnn-cu12/).
However, in CUDA 13 environments,
[nvidia-cudnn-cu13](https://pypi.org/project/nvidia-cudnn-cu13/) should
be installed.

The PR modifies `install_python_packages.sh` such that if CUDA 13 is
used, `nvidia-cudnn-cu13>=9.12.0.46` is installed (note that
[9.12.0.46](https://pypi.org/project/nvidia-cudnn-cu13/#history) is the
earliest version)

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Author: bkryu

docker/install/install_python_packages.sh

@@ -25,4 +25,15 @@ CUDA_VERSION=${1:-cu128}
 pip3 install torch --index-url https://download.pytorch.org/whl/${CUDA_VERSION}
 pip3 install requests ninja pytest numpy scipy build nvidia-ml-py cuda-python einops nvidia-nvshmem-cu12
 pip3 install nvidia-cutlass-dsl
-pip3 install 'nvidia-cudnn-frontend>=1.13.0' 'nvidia-cudnn-cu12>=9.11.0.98'
+pip3 install 'nvidia-cudnn-frontend>=1.13.0'
+
+# Install cudnn package based on CUDA version
+if [[ "$CUDA_VERSION" == *"cu13"* ]]; then
+    CUDNN_PACKAGE="nvidia-cudnn-cu13>=9.12.0.46"
+else
+    CUDNN_PACKAGE="nvidia-cudnn-cu12>=9.11.0.98"
+fi
+
+if [[ -n "$CUDNN_PACKAGE" ]]; then
+    pip3 install $CUDNN_PACKAGE
+fi