fix(client): support batched notifications

[lavigneer]

As per the examples in the jsonrpc specification, it is valid to include only notifications in a batch.

rpc call Batch (all notifications):

--> [
        {"jsonrpc": "2.0", "method": "notify_sum", "params": [1,2,4]},
        {"jsonrpc": "2.0", "method": "notify_hello", "params": [7]}
    ]
<-- //Nothing is returned for all notification batches

This change adds support for handling this use case.

I ran into this while trying to leverage this library for a proof of conept I was working on a little while back,. My particular use case was using the client crate of this library to communicate with an existing service. I realized I never upstreamed this change and figured it might be useful to others.

I didn't see any contribution guidelines for this project, so please let me know if I'm missing any information. If you're not accepting external contributions I understand and can close this out. Thanks for your time.

[niklasad1]

Suggested change

[niklasad1]

Thanks, looks good

EDIT: just run cargo +stable fmt --all on your code to make the CI happy

[lavigneer]

Thanks, looks good

EDIT: just run cargo +stable fmt --all on your code to make the CI happy

Done and pushed. Thanks