WIP:Update Wormblight from Reaver's Infestation talent in Corrs/Rot.

Updates the handling of healing from the wormblight map effect.

Currently, the damage type used by the effect checks if a target has the 'worm' attribute, which is granted by the Infestation sustain. This means that if the sustain is stripped, it will no longer heal the Reaver. It also means that another actor with the Infestation sustain active will also be healed by the effect, even if it's worms were not the source of the wormblight.

We update the damage type to check if a target is the summoner of the source to determine healing, rather than checking for the 'worm' attribute.

Now, only the summoner of the worm that creates the effect will be healed by it, and healing will continue even if the sustain is deactivated.