chore: fix r profile

[bryanpaget]

Fixes the R Profile generation by replacing unreliable regex with robust regex.

jira: https://jirab.statcan.ca/browse/ZONE-465

[mathis-marcotte]

I'm a little bit concerned about doing an exit 1 here when it fails to get the r version or ubuntu version, as this would prevent the pod from spinning up completely.
If someone is only using python in their notebook for example, a failing R setup shouldn't prevent them from using their notebook.

I'm thinking that it may be more safe to do an if..else here? Like

if [ -z "$R_VERSION" ] || [ -z "$UBUNTU_CODENAME" ]; then
    echo "Error: Failed to detect environment variables for R profile."
else
    PPM_URL="https...."
    ....
fi

That way, we at least log the problem and we have a trace of it when debugging if an error occurs, but it won't prevent the pod from starting.

But I am open to your thoughts on this!

[bryanpaget]

Good idea.

[mathis-marcotte]

I noticed you changed the command from a cat > to cat >> command, which means this now appends to the file instead of overwriting the file.

I don't see an immediate issue with this since this file should not be on persistent storage, so it should be resulting the same (and I tested with a notebook restart to confirm this). And this keeps our start up script a bit cleaner by avoid having to re-write the "plot_mimetypes" line.
I just wanted to comment on this point, I am not asking for a change here unless you feel the need to revert back.

[bryanpaget]

During my testing, I realized we already had an Rprofile.site, so I wanted to append to it rather than just overwrite it.

[mathis-marcotte]

LGTM

Tested on artifactory.cloud.statcan.ca/das-aaw-docker/jupyterlab-cpu:1a3b17065fa35de39f03eb47bd2733d0918cd424

Was able to successfully install an R package with install.packages("janitor") (using R studios)