[Spells] Normal Group Spells (non-raid) landed twice on caster

[noudess]

Description

When casting group buffs (in a non-raid situation) the spell was being cast twice on the original caster.

Type of change

• Bug fix (non-breaking change which fixes an issue)

Testing

Before this fix, casting a spell like Pack Chloroplast or Group Resist magic landed on caster twice:

https://cdn.discordapp.com/attachments/736008216906825858/1224719140967944344/image.png?ex=661e8395&is=660c0e95&hm=191e4a949c1bec0404688f911619dda8a16ae7b690898092d39b7bf0dde4e6c4&

I tested after the fix. I also went in and made sure this did not impact raids or non-grouped cases. I also found and deleted a comment in Groups::CastGroupSpell() that was incorrect, and removed a line commented out long ago.

Clients tested: RoF2

Checklist

• I have tested my changes
• I have performed a self-review of my code. Ensuring variables, functions and methods are named in a human-readable way, comments are added only where naming of variables, functions and methods can't give enough context.
• I own the changes of my code and take responsibility for the potential issues that occur