feat: Implement `XcmPaymentApi` for testnet and devnet.

Currently [`XcmPaymentApi`](https://github.com/r0gue-io/pop-node/blob/27f09da4db9f0b579a22369b1c4a2017c93c3ec5/runtime/mainnet/src/apis.rs#L329) is only implemented for mainnet runtime. If it is present in mainnet it should also be in every other runtime.