Method firmwareVersion

tests/deploy/main.cpp:189–189

@brief Firmware version */

    std::string chargePointVendor() const override { return ""; }
    /** @brief Firmware version */
    std::string firmwareVersion() const override { return ""; }
    /** @brief ICCID of the moden's SIM card */
    std::string iccid() const override { return ""; }
    /** @brief IMSI of the moden's SIM card */