Bump pyglet to 2.1.dev6

Author: pushfoo

pyproject.toml

@@ -23,7 +23,7 @@ dependencies = [
     # at the cost of slow download and constant pip install -I -e .[dev]    
     # "pyglet@git+https://github.com/pyglet/pyglet.git@development#egg=pyglet",
     # Expected future dev preview release on PyPI (not yet released)
-    'pyglet==2.1.dev5',
+    'pyglet==2.1.dev6',
     "pillow~=10.4.0",
     "pymunk~=6.8.1",
     "pytiled-parser~=2.2.5",