Document how to use `dapr publish` or http equivalent when using docker compose locally

**What content needs to be created or modified?**
[On the pubsub/How to: Publish a message and subscribe to a topic](https://docs.dapr.io/developing-applications/building-blocks/pubsub/howto-publish-subscribe/#publish-a-message) page

**Describe the solution you'd like**
Document how to use `dapr publish` or equivalent HTTP call when service and daprd is run using docker compose.

When you aren't publishing a message from another service hosted in your docker compose services, it's unclear how to initiate that receiver from development environment

**Where should the new material be placed?**
[](https://docs.dapr.io/developing-applications/building-blocks/pubsub/howto-publish-subscribe/#publish-a-message)