Bump the simulator to sr2023.2

See https://github.com/srobo/competition-simulator/releases/tag/sr2023.2
for the changes this brings.

Author: PeterJCLaw

simulator/index.md

@@ -33,7 +33,7 @@ local development you will need to install these yourself.
 ### Installing the simulation
 
 1. Create a directory, perhaps called `simulation` where you will store your robot code.
-2. [Download the simulation](https://github.com/srobo/competition-simulator/releases/download/sr2023.1/competition-simulator-sr2023.1.zip)
+2. [Download the simulation](https://github.com/srobo/competition-simulator/releases/download/sr2023.2/competition-simulator-sr2023.2.zip)
   and unzip it as a subdirectory of that directory:
   ```
   simulation