update python docs (#1436)

Author: matea16

pages/custom-query-modules/python.mdx

@@ -55,7 +55,7 @@ inside a Docker container, run the following command in the terminal:
 
 
 ```
-docker exec -i -u root <container_id> bash -c "apt install -y python3-pip &&
+docker exec -i -u memgraph <container_id> bash -c "apt install -y python3-pip &&
 pip install pandas"
 ```
 
@@ -69,16 +69,16 @@ commands in the Dockerfile:
 ```
 FROM memgraph/memgraph:latest
 
-USER root
+USER memgraph
 
 RUN apt install -y python3-pip
 RUN pip install pandas
 
-USER memgraph
 ```
 
-It is important that you install Python library as a `root` user, rather than
-the default `memgraph` user.
+Python libraries should now be installed as the `memgraph` user, which is the
+default user inside the Memgraph container. You no longer need to switch to the
+`root` user to perform installations.
 
 ## Example