Add vacuum variant to match without vacuum name

[duhow]

❗ NOTE: This adds a new slot_combination to Vacuum in intents.yaml, in order to skip specifying a name.

As the vacuum may have a different name than "vacuum", users will not trigger it by the entity name, but rather as "vacuum". This either forces the user to set an alias to the vacuum (named vacuum) to start it, or specify the full name for it.

[tetele]

I don't think this will work without some modifications on the core repo, so that the concerned intents know how to handle no slots.