docs(quickstart): Clarify docker command for macOS (#612)

Clarify docker command for macOS

I had issues when running the command on my m2 macbook air. [It turns
out][1] that apparently docker desktop on macOS doesn't really support
the host option.

Additionally, it looks like I had to explicitly pass the port mapping
options for the ports to be actually mapped.

There might be a better and more efficient solution, but this is what I
came up with and it finally worked.

[1]:docker/for-mac#1031

docs/quick-start/README.md

@@ -14,10 +14,20 @@ If you do not have docker on your machine, [Install Docker](https://docs.docker.
 
 ## Step 1
 
+### On linux
+
 ```bash
 docker run --network=host --ulimit memlock=-1 docker.dragonflydb.io/dragonflydb/dragonfly
 ```
 
+### On macOS
+
+_`network=host` doesn't work well on macOS, see [this issue](https://github.com/docker/for-mac/issues/1031)_
+
+```bash
+docker run --p 6379:6379 --ulimit memlock=-1 docker.dragonflydb.io/dragonflydb/dragonfly
+```
+
 Dragonfly DB will answer to both `http` and `redis` requests out of the box!
 
 You can use `redis-cli` to connect to `localhost:6379` or open a browser and visit `http://localhost:6379`