carto.PLACEKEY_TOH3 occasionally produces invalid H3s on Snowflake

[iasymmetric]

On Snowflake, carto.PLACEKEY_TOH3 occasionally returns incorrect and invalid H3s for valid placekeys.

As an example the placekey "@8f3-tw4-evz" maps to the H3 index "8a44516b382ffff" (this can be confirmed with the placekey api) which is a valid index, however carto.PLACEKEY_TOH3 returns the H3 "8a44516b2fc3fff" which is an invalid index.

This issue appears to be quite rare (appearing roughly on the order of 1 every 100k - 1M placekeys)