Does CSV still get created even if automated Google Sheets options is set?

I ran Lighthouse Parade with the `--output google-sheets` option.

I stepped away from my computer because an audit can take hours. I forgot to disable my laptop's sleep feature.

I then came back, and saw this error:
```
FetchError: Invalid response body while trying to fetch https://sheets.googleapis.com/v4/spreadsheets/1QF4KmnIF6HYJ2Fdi4qZLV-87EpENzgblG_fMuYWwS_4/values/%27Lighthouse%20Results%27%21A409?valueInputOption=USER_ENTERED: read ECONNRESET
```

The Google Sheet was not being written to anymore.

How can we gracefully handle this use case?
Does a CSV still get created, or does the whole process stop?

## An idea

At least a CSV gets created and some message/notification somewhere telling me along the lines of: "The Google Sheet write isn't working anymore, but no worries, you'll still get a CSV that you can [manually import](link to docs)".

Start by tracing the --output google-sheets entry point and the existing CSV-generation path; the issue does not name specific files or tests. Reproduce an interrupted Google Sheets request and determine whether processing stops, then define and test the intended CSV fallback and user notification behavior.

Written by the indexing model from the issue text.