fix issue #8259 - rupture applying multiple times

[majochem]

Fixes #8259 .

Description of the problem being solved:

The global Rupture debuff was not previously not assigned an effect name. Because of that, multiple instances were allowed to apply, as they had different active skills as their source.

I just assigned an effect name, which caused the standard mergeBuff / match functions to be able to properly identify duplicates and only apply the highest values instead.

Steps taken to verify a working solution:

• Checked number of applied stacks, effect on duration and damage for correctness
• Checked that different magnitudes from support gem level work correctly
• Checked that behavior is consistent across different skills

Link to a build that showcases this PR:

https://pobb.in/70IX7nLOCxOZ

Before screenshot:

After screenshot: