Align file names in getting_started.md

While running throught the tutorial
(https://docs.ray.io/en/latest/serve/getting_started.html#getting-started),
I was confused by the mismatch of the file names mentioned
in the markdown explanations and the file names stated in
the first line of the imported source files.
This tries to fix the mismatch by changing the markdown. Alternatively, the imported source files could be changed.

Signed-off-by: Alexander Junge <alexander.junge@gmail.com>

doc/source/serve/getting_started.md

@@ -139,7 +139,7 @@ To test locally, we run the script with the `serve run` CLI command. This comman
 to our deployment formatted as `module:application`. Make sure to run the command from a directory containing a local copy of this script saved as `serve_quickstart.py`, so it can import the application:
 
 ```console
-$ serve run serve_quickstart:translator_app
+$ serve run serve_deployment:translator_app
 ```
 
 This command will run the `translator_app` application and then block, streaming logs to the console. It can be killed with `Ctrl-C`, which will tear down the application.
@@ -223,10 +223,10 @@ We define the full application as follows:
 deployment_graph = Summarizer.bind(Translator.bind())
 ```
 
-Here, we bind `Translator` to its (empty) constructor arguments, and then we pass in the bound `Translator` as the constructor argument for the `Summarizer`. We can run this deployment graph using the `serve run` CLI command. Make sure to run this command from a directory containing a local copy of the `serve_quickstart_composed.py` code:
+Here, we bind `Translator` to its (empty) constructor arguments, and then we pass in the bound `Translator` as the constructor argument for the `Summarizer`. We can run this deployment graph using the `serve run` CLI command. Make sure to run this command from a directory containing a local copy of the `graph.py` code:
 
 ```console
-$ serve run serve_quickstart_composed:app
+$ serve run graph:app
 ```
 
 We can use this client script to make requests to the graph: