refactor(Core/Combat): implement compatiblity layer for ResetAllThreat() (#11778)

* implement ResetAllThreat()

* .

src/server/scripts/Northrend/Ulduar/Ulduar/boss_flame_leviathan.cpp

@@ -1674,7 +1674,7 @@ public:
             if (!target || !caster)
                 return;
 
-            caster->getThreatMgr().resetAllAggro();
+            caster->getThreatMgr().ResetAllThreat();
             caster->GetAI()->AttackStart(target);    // Chase target
             caster->AddThreat(target, 10000000.0f);
         }

src/server/scripts/Northrend/Ulduar/Ulduar/boss_ignis.cpp

@@ -138,7 +138,7 @@ public:
                             heat->ModStackAmount(-1);
                         }
                         me->CastSpell(me, SPELL_MOLTEN, true);
-                        me->getThreatMgr().resetAllAggro();
+                        me->getThreatMgr().ResetAllThreat();
                     }
                 }
             }

src/server/scripts/Northrend/Ulduar/Ulduar/boss_thorim.cpp

@@ -1158,7 +1158,7 @@ public:
                         }
                     }
                 _playerAttack = true;
-                me->getThreatMgr().resetAllAggro();
+                me->getThreatMgr().ResetAllThreat();
                 me->CallForHelp(40.0f);
                 AttackStart(who);
             }