Restore abstract method and add type hint

Author: mwcraig

src/astro_image_display_api/interface_definition.py

@@ -269,13 +269,14 @@ def offset_by(self, dx: float | Quantity, dy: float | Quantity) -> None:
         """
         raise NotImplementedError
 
-    def zoom(self, val) -> None:
+    @abstractmethod
+    def zoom(self, val: float) -> None:
         """
         Zoom in or out by the given factor.
 
         Parameters
         ----------
-        val : int
+        val : float
             The zoom level to zoom the image.
             See `zoom_level`.
         """

tests/test_astro_image_display_api.py

@@ -24,6 +24,6 @@ def test_api_test_class_completeness():
 
 
     assert all(attr_present), (
-        "ImageWidgetAPITest is does not access these attributes/methods:\n "
+        "ImageWidgetAPITest does not access these attributes/methods:\n "
         f"{"\n".join(attr for attr, present in zip(required_attributes, attr_present) if not present)}. "
     )