AT command length computation does not take string quotes into account

Consider this example:

#[derive(Clone, AtatCmd)]
#[at_cmd("+CPIN", NoResponse, timeout_ms = 5_000, termination = "\r")]
pub struct EnterPin<'a> {
    #[at_arg(len = 4)]
    pub pin: &'a str,
}

#[cfg(test)]
mod tests {
    use atat::AtatCmd;

    use super::*;

    #[test]
    fn can_enter_pin() {
        let cmd = EnterPin { pin: "1234" };
        assert_eq!(b"AT+CPIN=\"1234\"\r", cmd.as_bytes());
    }
}

The test panics because the string allocation does not take into account the two ". If at_arg(len = 6) was specified instead the test would pass. From what I can see from e.g. https://github.com/BlackbirdHQ/ublox-cellular-rs/blob/961d7f570204ae53bd90d5f4dc174097056b4d06/ublox-cellular/src/command/device_lock/mod.rs#L29 the length specified by at_arg() should be the string length and not the quoted string length.

FactbirdHQ / atat

AT command length computation does not take string quotes into account #136