Greetings @ObiTwo,
This sounds like the same issue as here: Problem with tutorial "Build and Run your First Python Application"
As seen in the marked solution on that post the templates have been updated to use docker compose going forward. You can see this now if you use the early access version of the extension and update the templates, or just wait a bit as this fix will be in the upcoming V2.4.0 release of the extension.
You could also manually modify the tasks.json in your project to use docker compose instead of docker-compose.
Best Regards,
Jeremias