ci: rebase before release push in manual_version_docs

Adds `pull: '--rebase --autostash'` to the EndBug/add-and-commit step
that pushes versioned docs, avoiding push failures when the branch has
moved ahead.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: B4nan

.github/workflows/manual_version_docs.yaml

@@ -126,6 +126,7 @@ jobs:
           default_author: github_actions
           # `actions/checkout` detaches HEAD on SHA refs; EndBug needs a branch to push.
           new_branch: ${{ github.event.repository.default_branch }}
+          pull: '--rebase --autostash'
 
       - name: Resolve output commitish
         id: resolve_commitish