Update next-steps.rst

Added note about running the worker in the directory above proj. If the worker is run within the proj directory resolving the error isn't intuitive from the resulting message

docs/getting-started/next-steps.rst

@@ -70,7 +70,7 @@ you simply import this instance.
 Starting the worker
 -------------------
 
-The :program:`celery` program can be used to start the worker:
+The :program:`celery` program can be used to start the worker (you need to run the worker in the directory above proj):
 
 .. code-block:: bash