CI:GHA:docs: Preface jobs with "docs-"
CI:GHA:docs: Preface jobs with "docs-"

Need to change the "html" and "pdf" jobs to be "docs-html"
and "docs-pdf" so it is clear what the jobs are on the branch
protection page which only shows the job name and not the workflow.

scottclowe/python-ci,scottclowe/python-continuous-integration,scottclowe/python-ci,scottclowe/python-continuous-integration