Sidecar Example README: Switch to relative paths (#617)

Just to avoid fragility with updates to examples breaking past release
examples, I switched the README on this example to using relative links,
so that people didn't end up being directed to pull from main, which
will likely break at some point.

Work on #546

examples/agones-xonotic/README.md

@@ -1,13 +1,14 @@
 # Agones & Xonotic Example
 
-An example of running [Xonotic](https://xonotic.org/) with Quilkin on an [Agones](https://agones.dev/) cluster.
+An example of running [Xonotic](https://xonotic.org/) with Quilkin on an [Agones](https://agones.dev/) cluster, 
+utilising the sidecar integration pattern.
 
 To interact with the demo, you will need to download the Xonotic client.
 
 ## Sidecar with no filter
 
-Run `kubectl apply -f https://github.com/googleforgames/quilkin/blob/main/examples/agones-xonotic/sidecar.yaml` to 
-create a Fleet of Xonotic dedicated game servers, with traffic processed through a Quilkin sidecar proxy.
+Run `kubectl apply -f ./sidecar.yaml` 
+to create a Fleet of Xonotic dedicated game servers, with traffic processed through a Quilkin sidecar proxy.
 
 This is particularly useful if you want to take advantage of the inbuilt metrics that Quilkin provides without 
 having to alter your dedicated game server.
@@ -18,7 +19,7 @@ Connect to the Agones hosted Xonotic server via the "Multiplayer > Address" fiel
 
 ## Sidecar with compression filter
 
-Run `kubectl apply -f https://github.com/googleforgames/quilkin/blob/main/examples/agones-xonotic/sidecar-compress.yaml`
+Run `kubectl apply -f ./sidecar-compress.yaml`
 to create a Fleet of Xonotic dedicated game servers, with traffic processed through a Quilkin sidecar proxy, 
 that is configured to decompress UDP traffic with the [Snappy](https://crates.io/crates/snap) 
 compression format.