Run Ma'at experiments automatically before releases

[integraledelebesgue]

It would be useful for us if experiments started automatically before our releases, e.g. when a pull request from a release branch is submitted in Scarb or in Foundry. They can be dispatched using features of GitHub Actions.

Warning

Dispatching experiments automatically can potentially slow down important, high-priority experiments we run manually (e.g. when fixing important bugs during releases). We need to investigate the potential risks.