Broken examples in docs

[danvratil]

The include-markdown plugin seems broken, nothing gets included and the entire page is broken.

It seems to work in mkdocs serve but is broken in production build.

List of broken pages:

https://qcoro.dvratil.cz/reference/core/qfuture/
https://qcoro.dvratil.cz/reference/core/qprocess/
https://qcoro.dvratil.cz/reference/core/qthread/
https://qcoro.dvratil.cz/reference/network/qabstractsocket/
https://qcoro.dvratil.cz/reference/network/qnetworkreply/
https://qcoro.dvratil.cz/reference/network/qtcpserver/
https://qcoro.dvratil.cz/reference/dbus/qdbuspendingcall/
https://qcoro.dvratil.cz/reference/dbus/qdbuspendingreply/