feat: optimize Docker image size (#6)

Dockerfile

@@ -1,6 +1,6 @@
 # syntax=docker/dockerfile:1
 ARG PYTHON_VERSION=3.8
-FROM python:$PYTHON_VERSION-slim AS base
+FROM python:$PYTHON_VERSION-slim
 
 # Install wget.
 RUN apt-get update && \
@@ -11,7 +11,8 @@ RUN apt-get update && \
 # Install Miniconda.
 RUN CONDA_ARCH=$([ "$TARGETARCH" = "arm64" ] && echo "aarch64" || echo "x86_64") && \
     wget --quiet "https://repo.anaconda.com/miniconda/Miniconda3-latest-Linux-$CONDA_ARCH.sh" --output-document ~/miniconda.sh && \
-    /bin/bash ~/miniconda.sh -b -p /opt/conda
+    /bin/bash ~/miniconda.sh -b -p /opt/conda && \
+    rm ~/miniconda.sh
 ENV PATH=/opt/conda/bin:$PATH
 ENV LD_LIBRARY_PATH=/opt/conda/lib:$LD_LIBRARY_PATH
 
@@ -20,4 +21,5 @@ ARG CUDA_VERSION=11.8
 ARG CUDNN_VERSION=8.8
 RUN conda install --name base conda-libmamba-solver && \
     conda config --set solver libmamba && \
-    conda install --channel conda-forge --yes cudatoolkit="$CUDA_VERSION" cudnn="$CUDNN_VERSION"
+    conda install --name base --channel conda-forge --yes cudatoolkit="$CUDA_VERSION" cudnn="$CUDNN_VERSION" && \
+    conda clean --all --force-pkgs-dirs --yes