net: golioth: Kconfig for max CBOR RPC response

[szczys]

Introduce GOLIOTH_RPC_MAX_RESPONSE_LEN which allows applications to change the max size of the CBOR response returned from an RPC method. This solves the issue of receiving an error when the RPC response is too large: golioth: QCBOREncode_FinishGetSize error: 1 (QCBOR_ERR_BUFFER_TOO_SMALL)

[github-actions[bot]]

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