Correction to publish_docs workflow for branches

[UncleGrumpy]

The github actions/checkout@v4 only tracks the current branch, even when fetch-depth: 0 is used, this causes branch names other than the current one to be missed when creating the html navigation menus. This is solved by adding a step to track all of the remote branches that were fetched during checkout.

These changes are made under both the "Apache 2.0" and the "GNU Lesser General Public License 2.1 or later" license terms (dual license).

SPDX-License-Identifier: Apache-2.0 OR LGPL-2.1-or-later