chore(docs): temporarily override publish branch for docs

[dreamorosi]

Description of your changes

After the migration of the repo to the new org started in #1475, the idea is to remove GitHub Pages as destination. This is tracked in #1509. In the meanwhile, in order to avoid being unable to publish docs, I am overriding the configs related to GitHub Pages to be able to publish to the current branch designated for the docs (backup-gh-pages).

Related issues, RFCs

Issue number: #1509

Checklist

• My changes meet the tenets criteria
• I have performed a self-review of my own code
• I have commented my code where necessary, particularly in areas that should be flagged with a TODO, or hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my change is effective and works
• The PR title follows the conventional commit semantics

Breaking change checklist

Is it a breaking change?: NO

• I have documented the migration process
• I have added, implemented necessary warnings (if it can live side by side)

---

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

Disclaimer: We value your time and bandwidth. As such, any pull requests created on non-triaged issues might not be successful.