fix batch requests with ws

[baabeetaa]

Description

Batch Request is in spec of jsonrpc https://www.jsonrpc.org/specification#batch

This PR is a fix to make Batch Request working for websocket.

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[fedekunze]

Minor comments, can you also add tests?

[baabeetaa]

Minor comments, can you also add tests?

do you mean websocket tests?

[fedekunze]

ACK, would be great to add websocket tests

[fedekunze]

@baabeetaa can you update the PR?

[adisaran64]

@baabeetaa will add tests with this ticket, can update and merge this PR when possible

[baabeetaa]

i'll close this and update changes to #1342 with tests.