[TF2] Update the Halloween Spell attributes to appear blue during a Full Moon.

[FrozenDragon0]

Currently, the Halloween Spell attributes only appear blue during Halloween, October 1st up to November 7th however, the code responsible for this only checks for Halloween and not Full Moons, so when a Full Moon is active, the Halloween Spell attributes remain grayed out as if they aren't active, even though Halloween Spells can be used during a Full Moon. This was likely an oversight when spells were made to be visible during Full Moons.