Aspect ratio bug

Apologies if I haven't understood how resizing works with PIL. With this the following bit of the (original) code, it seems you set `aspect_ratio = width / height`, but when comparing, you swap the two. Reason I have swapped the two is because in the first line you have `width, height = image.size`
```python
width, height = image.size
max_dim = max(width, height)
if max_dim < 512:
im_size = (378, 378)
else:
aspect_ratio = width / height
im_size = min(
self.supported_sizes,
key=lambda size: (
abs((size[1] / size[0]) - aspect_ratio),
abs(size[0] - width) + abs(size[1] - height),
),
)
```

vision_encoder.py

@@ -233,7 +233,7 @@ class VisionEncoder(nn.Module):
             im_size = min(
                 self.supported_sizes,
                 key=lambda size: (
-                    abs((size[1] / size[0]) - aspect_ratio),
+                    abs((size[0] / size[1]) - aspect_ratio),
                     abs(size[0] - width) + abs(size[1] - height),
                 ),
             )