Fix Glacial Hammer of Shattering missing crit chance every 3rd use (#8931)

The skill critically strikes every 3rd use but we were not calculating that at all

Co-authored-by: LocalIdentity <localidentity2@gmail.com>

src/Data/Skills/act_str.lua

@@ -4994,6 +4994,11 @@ skills["GlacialHammerAltX"] = {
 	},
 	statDescriptionScope = "skill_stat_descriptions",
 	castTime = 1,
+	statMap = {
+		["additional_main_hand_hits_per_combo_average"] = {
+			flag("Every3UseCrit"),
+		},
+	},
 	baseFlags = {
 		attack = true,
 		melee = true,

src/Export/Skills/act_str.txt

@@ -897,6 +897,11 @@ local skills, mod, flag, skill = ...
 
 #skill GlacialHammerAltX
 #flags attack melee
+	statMap = {
+		["additional_main_hand_hits_per_combo_average"] = {
+			flag("Every3UseCrit"),
+		},
+	},
 #mods
 
 #skill VaalGlacialHammer