CI: Fix uploading docs from GitHub Actions
CI: Fix uploading docs from GitHub Actions

The main change is to bump the version of the plugin which fixed the bug
that was causing our problems. This also re-enables deleting some files
before deploying and makes clearing the target directory explicit.

Unidata/MetPy,dopplershift/MetPy,Unidata/MetPy,ShawnMurd/MetPy,dopplershift/MetPy