Upgrade actions to latest version

[confused-Techie]

The most recent runs of our deploy workflow are failing with the following error:

Secret source: Actions
Prepare workflow directory
Prepare all required actions
Getting action download info
Download action repository 'actions/checkout@v3' (SHA:f43a0e5ff2bd294095638e[18](https://github.com/pulsar-edit/documentation/actions/runs/13935837386/job/39003412046#step:1:22)286ca9a3d1956744)
Download action repository 'actions/setup-node@v3' (SHA:1a4442cacd436585916779262731d5b162bc6ec7)
Download action repository 'actions/configure-pages@v3' (SHA:b8130d9ab958b325bbde9786d62f2c97a9885a0e)
Download action repository 'actions/upload-pages-artifact@v1' (SHA:84bb4cd4b733d5c3[20](https://github.com/pulsar-edit/documentation/actions/runs/13935837386/job/39003412046#step:1:24)c9c9cfbc354937524f4d64)
Download action repository 'actions/deploy-pages@v2' (SHA:de14547edc9944350dc0481aa5b7afb08e75f254)
Getting action download info
Error: Missing download info for actions/upload-artifact@v3

It seems that this error is due to an older, no longer supported, version of actions/upload-pages-artifact. So I've gone ahead and in this PR bumped:

• actions/upload-pages-artifact
• actions/deploy-pages

I also looked further into the actions/configure-pages step and found it to not actually be needed, so I removed it.

According to that action's docs it's purpose is to A GitHub Action to enable Pages, extract various metadata about a site, and configure some supported static site generators., which of course we already have Pages enabled now, and no longer need this step.