chore: improve gh-pages publishing steps

[maribethb]

The basics

• I validated my changes

The details

Resolves

Fixes #9589

Proposed Changes

• Fixes the basic problems with the gh-pages gulp tasks (like the repo and branch names being wrong). Thanks Aaron!
• Removes some ancient unused gulp workflows
• Lets you specify which remote to push to
• Lets you opt to skip the part that syncs with main so you can stage some local github pages changes
• Adds a workflow for kicking off this process from github actions

Reason for Changes

Really annoying to debug these gulp scripts when it keeps stashing your changes!

Test Coverage

Tested locally as best as I could but I did not run the --upstream command locally.

Documentation

Additional Information