ReadOnlyClientInterface is not being created for CW721-base contract (Branch v0.16)

When trying to create the client for the cw721-base contract (branch v0.16!) the XxxReadOnlyInterface is not created.

Looking at the [schema file](https://github.com/CosmWasm/cw-nfts/blob/v0.16.0/contracts/cw721-base/schema/query_msg_for__empty.json)

`{
"$schema": "http://json-schema.org/draft-07/schema#",
"title": "QueryMsg_for_Empty",
"oneOf": [
{
"description": "Return the owner of the given token, error if token does not exist Return type: OwnerOfResponse",
[....]`

I noticed that when manually changing the title to (removing the "_for_Empty" part)

`
"title": "QueryMsg",
`

and running TS-codegen again also the XxxReadOnlyClientInterface is created properly.