fix: remove deprecated vision model from test

The model that this test uses is no longer available online. [1] [2]

Per the upstream commit, gpt-4o would be the next best candidate for
vision models, so use that instead.

[1]: https://github.com/BerriAI/litellm/pull/23400

[2]: c9f7075690

tests/basic/test_commands.py

@@ -924,7 +924,7 @@ class TestCommands(TestCase):
             self.assertEqual(len(coder.abs_read_only_fnames), 0)
 
             # Test with vision model
-            vision_model = Model("gpt-4-vision-preview")
+            vision_model = Model("gpt-4o")
             vision_coder = Coder.create(vision_model, None, io)
             vision_commands = Commands(io, vision_coder)