Use virtual env in code-style-check image

code-style-check/Dockerfile

@@ -4,13 +4,17 @@ LABEL maintainer="Ingo Meyer <i.meyer@fz-juelich.de>"
 ARG CLANG_FORMAT_VERSION="13"
 ARG CMAKE_FORMAT_VERSION="0.6.7"
 
+ENV PATH="/venv/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
+
 RUN apt-get update && \
     apt-get install -y --no-install-recommends "clang-format-${CLANG_FORMAT_VERSION}" file git python3-pip \
-                                               python3-setuptools python3-wheel && \
+                                               python3-venv python3-setuptools python3-wheel && \
     update-alternatives --install "/usr/bin/clang-format" \
                                   "clang-format" \
                                   "/usr/bin/clang-format-${CLANG_FORMAT_VERSION}" \
                                   1 && \
+    python3 -m venv /venv && \
+    python3 -m pip install -U pip setuptools wheel && \
     python3 -m pip install "cmake_format==${CMAKE_FORMAT_VERSION}" && \
     rm -rf /var/lib/apt/lists/*