Update package name in installation instructions

The package name 'overcooked-environment' mentioned in the installation instructions has been updated to 'cooperative_cuisine'. This change has been reflected in both the README.md and __init__.py files to ensure that users install the correct package named 'cooperative_cuisine' from the given repository.

README.md

@@ -53,7 +53,7 @@ You can replace the GUI with your own GUI (+ study server/matchmaking server).
 The correct environment needs to be active:
 
 ```bash
-pip install overcooked-environment@git+https://gitlab.ub.uni-bielefeld.de/scs/cocosy/overcooked-simulator@main
+pip install cooperative_cuisine@git+https://gitlab.ub.uni-bielefeld.de/scs/cocosy/overcooked-simulator@main
 ```
 
 #### Run

cooperative_cuisine/__init__.py

@@ -23,7 +23,7 @@ like a "real", cooperative, human partner.
 
 You need a Python **3.10** or newer environment.
 ```bash
-pip install overcooked-environment@git+https://gitlab.ub.uni-bielefeld.de/scs/cocosy/overcooked-simulator@main
+pip install cooperative_cuisine@git+https://gitlab.ub.uni-bielefeld.de/scs/cocosy/overcooked-simulator@main
 ```
 Or clone it and install it as an editable library which allows you to use all the scripts directly.
 ```bash