[fix][doc] auth problem in getting-started-docker-compose.md (#741)

* [fix][doc] auth problem in getting-started-docker-compose.md

* Update getting-started-docker-compose.md

* Update getting-started-docker-compose.md

---------

Co-authored-by: Lari Hotari <lhotari@users.noreply.github.com>

docs/getting-started-docker-compose.md

@@ -113,6 +113,13 @@ services:
 
 ## Step 2: Create a Pulsar cluster
 
+As preparation, create data directories and change the data directory ownership to uid(10000) which is the default user id used in the Pulsar Docker container.
+```bash
+sudo mkdir -p ./data/zookeeper ./data/bookkeeper
+# this step might not be necessary on other than Linux platforms
+sudo chown 10000 -R data
+```
+
 To create a Pulsar cluster by using the `compose.yml` file, run the following command.
 
 ```bash