Small typo on IntermediateLayerGetter (#4362)

torchvision/models/detection/backbone_utils.py

@@ -13,7 +13,7 @@ class BackboneWithFPN(nn.Module):
     Adds a FPN on top of a model.
     Internally, it uses torchvision.models._utils.IntermediateLayerGetter to
     extract a submodel that returns the feature maps specified in return_layers.
-    The same limitations of IntermediatLayerGetter apply here.
+    The same limitations of IntermediateLayerGetter apply here.
     Args:
         backbone (nn.Module)
         return_layers (Dict[name, new_name]): a dict containing the names