Core/DBC: Remove store getters (useless since we don't have scripts as external dll)

src/server/scripts/Commands/cs_achievement.cpp

@@ -67,7 +67,7 @@ public:
             return false;
         }
 
-        if (AchievementEntry const* achievementEntry = GetAchievementStore()->LookupEntry(achievementId))
+        if (AchievementEntry const* achievementEntry = sAchievementStore.LookupEntry(achievementId))
             target->CompletedAchievement(achievementEntry);
 
         return true;