Set pygame-gui version to exactly 0.6.9 as 0.6.10 tries to import a missing import from pygame

setup.py

@@ -16,7 +16,7 @@ requirements = [
     "scipy>=1.11.4",
     "pytest>=3",
     "pyyaml>=6.0.1",
-    "pygame-gui>=0.6.9",
+    "pygame-gui==0.6.9",
     "pydantic>=2.6.3",
     "fastapi>=0.109.2",
     "uvicorn>=0.27.0",