Node.js 12 Github Actions are deprecated (upgrade to node 16)

[jtkiley]

Github Actions is showing me the following warning:

Node.js 12 actions are deprecated. Please update the following actions to use Node.js 16: 
ResearchSoftwareActions/EnsureCleanNotebooksAction@1.1. For more information see: 
https://github.blog/changelog/2022-09-22-github-actions-all-actions-will-begin-running-on-node16-instead-of-node12/.

It looks like they want to have this moved over this summer, so it may be time sensitive to keep this working.

[jtkiley]

Looks like this will be enforced tomorrow:

Following on from our warning in workflows using Node12 we will start enforcing the use of Node16 rather than Node12 on the 14th of June.

See here.

Pinging @trallard, because you're the most recent committer (though it's been a bit).