Add underscores on `_hide_from_export_` in help documentation

[isalew]

In the section on reporting tool documentation, the Archi User Guide says hide_from_export, but should say _hide_from_export_ with underscores, as documented in the release version history.

The following line of code should be updated: https://github.com/archimatetool/archi/blob/1f90a1d484392b846c2f0e21dae4bf79971740f4/com.archimatetool.help/help/Text/reporting-html.html#L36

[Phillipus]

Thanks for raising this. I've corrected the error now so will close this one.

https://github.com/archimatetool/archi/blob/master/com.archimatetool.help/help/Text/reporting-html.html