Finalize transfer of plugin under tox-dev

[Sorin Sbarnea]

Steps needed for transfering

• repo move (while keeping my repo ownership)
• update repository links in setup.cfg
• invite toxdev bot user to be maintainer on pypi and testpypi servers
• generate repo-specific pypi login tokens for toxdev user and store them them as github secrets: TESTPYPI_PASSWORD and PYPI_PASSWORD. This enables github actions to publish releases.
• tag the first release using github releases page
• @ssbarnea to setup main branch: forbit pushes, enforce CI.