Use highest max shock from any active skill, not from main skill

[Lilylicious]

Fixes #6243

Description of the problem being solved:

Shock nova has +10% to max effect of shock. However, when using it as a secondary skill, other skills would not be able to set max shock to those 10% higher. This meant that you could not simulate DPS accurately of other skills in situations where your alternate shock nova is able to crit for the max.

This does introduce a potential user error where they use the main skill shock tooltips to try and calculate how much they shock, but there's only so much we can do about that.

Steps taken to verify a working solution:

• Main skill arc, secondary skill shock nova, set shock to 60%.
• Note that without the change, max shock was set to 50% for Arc and 60% for Shock Nova. Changing shock to 50% did not alter Arc damage.
• After change, max shock now lists at 60% for both skills. Changing shock to 50% alters damage of both.

Link to a build that showcases this PR:

https://pobb.in/L7s622aSaPUu