EOF is not propagated to SendInputB

[gescheit]

If a device closes connection during execution, Channel.read() just silently suppress EOF. It is defined here: https://github.com/scrapli/scrapligo/blob/31a4363eecf3e34ea4e44149cc5a90419f4d3171/channel/read.go#L55 introduced in PR https://github.com/scrapli/scrapligo/pull/109. In this way SendInputB() will wait for command timeout. Not only it is pointless waiting but also it hides real result. For example, if it is reboot command then receiving errTimeoutError is unclear whether the command was executed successfully or not. I think it should be like this:

            if errors.Is(err, io.EOF) {
                // the underlying transport was closed so just return
                c.Errs <- err
                return
            }

or

            c.l.Criticalf(
                "encountered error reading from transport during channel read loop. error: %s", err,
            )

            c.Errs <- err
            if errors.Is(err, io.EOF) {
                return
            }

[carlmontanari]

hey @gescheit seems reasonable to me -- are you up for a pr for this?