FYI, fixing the 'SpellEffect' compile error 5.4

[regecksqt]

I've noticed heaps of routines and bots are broken because `SpellEffect` got moved into another namespace. And since half these routines are copy pasta of each other, the fix is simple.

In the source files where `SpellEffect` (the class name, not the field name) is referenced, just add:

using Styx.WoWInternals.DBC;

to the imports section.