Added a missing cooldown bonus (#6118)

Fixes #6113

Thanks to @AsurielRO

db/re/item_combo_db.txt

@@ -951,7 +951,7 @@
 18776:22015,{ bonus bMatk,20; }
 18823:19246,{ .@atk = 40; .@aspd = 3; .@dmg = 2; .@agi = readparam(bAgi); if (.@agi > 107) { .@atk += 60; .@aspd += 5; .@dmg += 2; } if (.@agi > 119) { .@atk += 80; .@aspd += 7; .@dmg += 4; } bonus bBaseAtk,.@atk; bonus bAspdRate,.@aspd; bonus2 bSubRace,RC_Player_Human,.@dmg; bonus2 bResEff,Eff_Blind,10000; bonus2 bResEff,Eff_Silence,10000; }
 18823:28372,{ bonus2 bSkillVariableCast,"CR_GRANDCROSS",-2000; bonus2 bSkillAtk,"LG_RAYOFGENESIS",BaseLevel/30; bonus2 bSkillUseSP,"LG_RAYOFGENESIS",-10; bonus2 bSkillAtk,"CR_GRANDCROSS",BaseLevel; }
-18823:28551,{ bonus bLongAtkRate,getskilllv("LG_CANNONSPEAR")*2; bonus bLongAtkRate,getskilllv("LG_OVERBRAND")*2; bonus2 bSkillAtk,"LG_CANNONSPEAR",30; bonus2 bSkillAtk,"LG_OVERBRAND",20; }
+18823:28551,{ bonus bLongAtkRate,getskilllv("LG_CANNONSPEAR")*2; bonus bLongAtkRate,getskilllv("LG_OVERBRAND")*2; bonus2 bSkillAtk,"LG_CANNONSPEAR",30; bonus2 bSkillAtk,"LG_OVERBRAND",20; bonus2 bSkillCooldown,"LG_OVERBRAND",-2000; }
 18849:32237,{ .@r = getequiprefinerycnt(EQI_HEAD_TOP); bonus bFixedCast,-300; if (.@r > 0) { bonus bMatk,(10*.@r); if (.@r >= 7) { bonus2 bMagicAddRace,RC_DemiHuman,10; bonus2 bMagicAddRace,RC_Player_Human,10; bonus2 bMagicAddRace,RC_Demon,10; if (.@r >= 9) { bonus2 bMagicAtkEle,Ele_Water,10; bonus2 bMagicAtkEle,Ele_Wind,10; bonus2 bMagicAtkEle,Ele_Earth,10; bonus2 bMagicAtkEle,Ele_Fire,10; bonus2 bMagicAtkEle,Ele_Neutral,10; if (.@r >= 11) { bonus2 bMagicAddClass,Class_Boss,20; } } } } }
 18867:1720,{ bonus bLongAtkRate,3+(getequiprefinerycnt(EQI_HAND_R) > 6 ? 5:0); }
 18868:28320,{ bonus2 bAddRace,RC_DemiHuman,10; bonus2 bAddRace,RC_Player_Human,10; }