chore: updates mypy type hinting in geo_ops.py

Author: chalmerlowe

packages/bigframes/bigframes/core/compile/ibis_compiler/operations/geo_ops.py

@@ -182,8 +182,8 @@ def st_buffer(
 
 @ibis_udf.scalar.builtin
 def st_distance(
-    a: ibis_dtypes.geography,
-    b: ibis_dtypes.geography,
+    a: ibis_dtypes.geography,  # type: ignore
+    b: ibis_dtypes.geography,  # type: ignore
     use_spheroid: bool,  # type: ignore
 ) -> ibis_dtypes.float:  # type: ignore
     """Convert string to geography."""