bug: ts-codegen fails to generate correct bindings

### What is happening
Cw3 Fixed Multisig has `Vote` as both an `ExecuteMsg` and a `QueryMsg`:
* https://github.com/CosmWasm/cw-plus/blob/main/contracts/cw3-fixed-multisig/src/msg.rs#L29-L32
* https://github.com/CosmWasm/cw-plus/blob/main/contracts/cw3-fixed-multisig/src/msg.rs#L59-L60

When you generate the TS bindings for the Cw3 contract:
```
cosmwasm-ts-codegen
? [cmd] what do you want to do? generate
? [schema] which directory contains the the Rust contracts? ./schema
? [out] where is the output directory? ./ts
? [name] contract name? Cw3FixedMultisig
? [plugin] which plugins? client, message-composer
? [bundle] enable bundle? No
```
It ends up generating the bindings where the `vote` property on `Cw3FixedMultisigReadOnlyInterface` gets overridden by the `vote` property on `Cw3FixedMultisigInterface` with a different syntax.

### Expectation
The Cw3 contract is correct. `ts-codegen` should be able to correctly handle this edge case when the names across Execute and Query msgs might conflict.