Install pipenv.

.devcontainer/Dockerfile

@@ -13,7 +13,7 @@ RUN mkdir -p /usr/share/man/man1
 RUN apt-get update \
     # Verify git, process tools, lsb-release (common in install instructions for CLIs) installed
     && apt-get -y install git wget vim-tiny openssh-client less iproute2 procps lsb-release \
-    && apt-get -y install build-essential python3-venv \
+    && apt-get -y install build-essential python3-venv pipenv \
     #
     # Create a non-root user
     && groupadd --gid $USER_GID $USERNAME \