This may easily be due to manually installing some dependencies and installing others using dnf. You did not state how things were installed nor give details of the steps taken.
I do not use webkit so have no clue about the actions needed. In general the best approach is to install using dnf with either an app available in the fedora repo or another suitable repo that provides all the appropriate dependencies so you do not have to piece-meal the install.
If you provide more info and not just a generalization as in the line quoted above it would be helpful so we can help you.
That’s for installing dependencies so that you can build an RPM from source; I doubt you really needed to do this. RPMs are binaries and you generally don’t build them locally.
