Bug Fix: Cast from QByteArray to std::runtime_error

Created by: itay-grudev

I am compiling this on a sligthtly older Qt version (Qt 5.6) with a slightly older compiler and I encounter the following error:

error: no matching conversion for functional-style cast from 'QByteArray' to 'std::runtime_error'

This is easily mitigated and the solution is forward-compatible. The problem is simply because of mising cast operator from QByteArray to std::string on older Qt version. This solution should support all Qt versions.

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