a follower, sub, or bits goal begins.

### Goal
- `[[[event.type]]]` :: "follower", "subscription", "subscription_count", "new_subscription", or "new_subscription_count"
- `[[[event.description]]]` :: Goal description (your custom text)
- `[[[event.current_amount]]]` :: Starting amount (where the goal begins from)
- `[[[event.target_amount]]]` :: Target to hit
- `[[[event.started_at]]]` :: When the goal started

note: maps to the Twitch EventSub event `channel.goal.begin`.