The "addresses" field was confusing because it refered to public keys
using their P2PKH address. It was included in the return object when
needed for backward compatibility. Remove that compatibility now that
the -deprecatedrpc=validateaddress option has been removed.
New applications should use the 'embedded'->'address' field for P2SH or
P2WSH wrapped addresses, and 'pubkeys' for inspecting multisig
participants.
https://github.com/bitcoin/bitcoin/pull/15750/commits/b4338c151d4788c33f4b7c54daaf7f94b193a624
---
Backport of Core PR15750