Short answer
Likely fine. A small taste of passion fruit pulp is generally safe for dogs. The real risk comes from the peel, which contains natural toxins, but sauces usually only use the pulp. Just watch for any vomiting or diarrhea over the next few hours. If those signs appear, give your regular vet a call.
Passion fruit — Food safety facts
Feed with care · Dogs · full breakdown on the linked food page
A teaspoon of pulp is fine. The peel and leaves contain cyanogenic glycosides and should never be eaten.
The full verdict, portion guidance and serving notes are collected on the Passion fruit food facts page.