Add r-renv and clean up

[bryanpaget]

I've added one package, r-renv, but in the process in merged these two mamba package installation blocks. See below code snippets.

We tend to have too many RUN blocks for packages.

• 6_rstudio.Dockerfile#L15

RUN mamba install --quiet --yes \
      'r-rodbc' \
      'r-tidyverse' \
      'r-arrow' \
      'r-aws.s3' \
      'r-catools' \
      && \
      clean-layer.sh && \
      fix-permissions $CONDA_DIR && \
      fix-permissions /home/$NB_USER

# Install some default R packages
RUN mamba install --quiet --yes \
      'r-hdf5r' \
      'r-odbc' \
      'r-sf' \
      'r-e1071' \
      'r-markdown' \
    && \
    clean-layer.sh && \
    fix-permissions $CONDA_DIR && \
    fix-permissions /home/$NB_USER

So I merged these two into one.

• 6_rstudio.Dockerfile#L15

# Install some default R packages
RUN mamba install --quiet --yes \
      'r-arrow' \
      'r-aws.s3' \
      'r-catools' \
      'r-e1071' \
      'r-hdf5r' \
      'r-markdown' \
      'r-odbc' \
      'r-renv' \
      'r-rodbc' \
      'r-sf' \
      'r-tidyverse' \
    && \
    clean-layer.sh && \
    fix-permissions $CONDA_DIR && \
    fix-permissions /home/$NB_USER

[Souheil-Yazji]

Don't forget to check upstream images for r-env

[Souheil-Yazji]

LGTM