plug tiny coverage holes

Author: d-v-b

src/zarr/core/array.py

@@ -698,7 +698,7 @@ async def _create(
                 overwrite=overwrite,
             )
         else:
-            raise ValueError(f"Insupported zarr_format. Got: {zarr_format}")
+            raise ValueError(f"zarr_format must be 2 or 3, got {zarr_format}")  # pragma: no cover
 
         if data is not None:
             # insert user-provided data

src/zarr/core/indexing.py

@@ -173,8 +173,8 @@ def iter_grid(
         return itertools.product(*(dimensions))
 
     else:
-        msg = f"Indexing order {order} is not supported at this time."  # type: ignore[unreachable]
-        raise NotImplementedError(msg)
+        msg = f"Indexing order {order} is not supported at this time."  # type: ignore[unreachable] # pragma: no cover
+        raise NotImplementedError(msg) # pragma: no cover
 
 
 def iter_regions(