Fix gem group counting logic

[moxaj]

Description of the problem being solved:

Before, when you had a granted skill from an item / tree, and disabled that socket group, it would be counted towards the limit of 9.

Steps taken to verify a working solution:

• equip 9 Arc gems, each in its own group
• equip Sadist's Mercy Flanged Mace
• disable the granted Harbinger of Madness
• verify that there is no warning message for going over the limit of 9
• add another socket group with Arc and Ice Nova (in the same group)
• verify that there's a warning for the limit iff the socket group is enabled and at least one of Arc and Ice Nova is enabled

[LocalIdentity]

I simplified the fix