Fix: Fix weighted centroid calculation (#393)

The third bug found when looking into
#390.

I can't believe I'd never hit this before, but I was using the x
coordinate values to update the _y_ value of the weighted centroid. So
you'd potentially get this error for any large datasets in the western
hemisphere.

Author: kylebarron

lonboard/_cli.py

@@ -11,9 +11,6 @@
 
 from lonboard import viz
 
-# path = Path("/Users/kyle/github/developmentseed/lonboard/DC_Wetlands.parquet")
-# path = Path("/Users/kyle/Downloads/UScounties.geojson")
-
 
 def read_pyogrio(path: Path) -> pa.Table:
     """Read path using pyogrio and convert field metadata to geoarrow

lonboard/_geoarrow/ops/centroid.py

@@ -73,7 +73,7 @@ def update_coords(self, coords: pa.FixedSizeListArray):
         new_chunk_modifier = new_chunk_len / (self.num_items + new_chunk_len)
 
         new_chunk_avg_x = np.mean(np_arr[:, 0])
-        new_chunk_avg_y = np.mean(np_arr[:, 0])
+        new_chunk_avg_y = np.mean(np_arr[:, 1])
 
         existing_x_avg = self.x
         existing_y_avg = self.y