Build and deploy from the devel branch once a week, preferably at the start of the week

Follows on from https://github.com/ansible/ansible-documentation/issues/2047

The workflow to build the package docs should run once a week and deploy the `devel` branch of this repository to the `devel` of the [package-doc-builds](https://github.com/ansible-community/package-doc-builds/tree/devel) repository.