Update CI to use latest versions of cache/other actions

[njtierney]

There are some warnings:

macOS-latest, tf-default, R-release
The following actions uses node12 which is deprecated and will be forced to run on node16: actions/checkout@v2, actions/cache@v2. For more info: https://github.blog/changelog/2023-06-13-github-actions-all-actions-will-run-on-node16-instead-of-node12-by-default/

Which are coming up during CI runs, suggesting I need to update actions like checkout and cache.

Take a look at https://github.com/tidyverse/dplyr/blob/main/.github/workflows/R-CMD-check.yaml to see what the current state-of-the-art is.

[njtierney]

This has been solved in #740 but this issue didn't close properly