Create manually-triggered GitHub Action to regenerate phrase translation

[eddieantonio]

We want to be able to trigger a regeneration of the automatic phrase translations through a GitHub Action. This will use the existing deploy.altlab.dev to issue a management command (maybe after UAlbertaALTLab/deploy.altlab.dev#9 is implemented). If the management command fails, the deploy fails, and whoever is interested in the GitHub Action working will be notified.

@andrewdotn, please let me know if this is what you were thinking.