Fix: Correct --add-host Flag Format in README (#1767)

This PR updates the README to correct the format of the --add-host flag used in the Docker run command.
The previous format, host.docker.internal=host-gateway, was incorrect and resulted in the following error:
invalid argument "host.docker.internal=host-gateway" for "--add-host" flag: bad format for add-host: "host.docker.internal=host-gateway"
Use code with caution.
This PR fixes the issue by updating the flag to the correct format:
--add-host host-gateway:host.docker.internal
Use code with caution.
This ensures that the Docker container can correctly resolve the host.docker.internal hostname to the host machine's gateway IP address.

README.md

@@ -59,7 +59,7 @@ docker run \
     -v $WORKSPACE_BASE:/opt/workspace_base \
     -v /var/run/docker.sock:/var/run/docker.sock \
     -p 3000:3000 \
-    --add-host host.docker.internal=host-gateway \
+    --add-host host.docker.internal:host-gateway \
     ghcr.io/opendevin/opendevin:0.5
 ```