Fix issue with optional rpc parameters.

[Neopallium]

This change allows correct handling of Option<T> rpc parameter types. The filter was removing all null values, but those are needed for Option<T> parameters. The isOptional: true can't be used when mixing optional parameters with required parameters.

[Neopallium]

An example of an RPC endpoint that has this issue see the asset.canTransfer endpoint for Polymesh: https://polkadot.js.org/apps/?rpc=wss%3A%2F%2Fmainnet-rpc.polymesh.network#/rpc

Leave the from_custodian and to_custodian parameters unset. You can use 0x for the did fields and for the ticker, or just leave them empty.

[TarikGul]

Closing since https://github.com/polkadot-js/apps/pull/9911 resolves this.

[polkadot-js-bot]

This pull request has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.