Update pydantic version in setup.py

The setup.py file has been modified to require a more up-to-date version of the pydantic package. It has been updated from version 2.5.3 to 2.6.3.

setup.py

@@ -17,7 +17,7 @@ requirements = [
     "pytest>=3",
     "pyyaml>=6.0.1",
     "pygame-gui>=0.6.9",
-    "pydantic>=2.5.3",
+    "pydantic>=2.6.3",
     "fastapi>=0.109.2",
     "uvicorn>=0.27.0",
     "websockets>=12.0",