tools/publish-doc: enable pushing docs for specific tags

Historically, I copied the docs on the server directly after pushing latest,
but (especially with meson) it's a lot easier to just build that specific tag
locally and rsync it to the correct target directory.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
51 jobs for wip/doc-pusher in 5 minutes and 19 seconds (queued for 4 seconds)
latest