Improve release checklist for deb repo

[ci skip]

Author: gaborcsardi

tools/RELEASE.md

@@ -31,7 +31,8 @@
 - [ ] Test the macOS installers. (The rest are tested in the CI.)
 - [ ] `git commit` with the NEWS and README updates, update tag, push to GH,
       `--tags` as well.
-- [ ] Update Debian repo, by running the Action manually.
+- [ ] Update Debian repo, by running the Action manually, and then `pull --rebase` and push the
+      `gh-pages` branch to the server at DigitalOcean.
 - [ ] Update homebrew repo.
 - [ ] Update choco package.
     - Make sure `rig.nuspec` is current