feat(Core/Maps): Implement dynamic respawn rates (#21417)

Co-authored-by: r00ty-tc <r00ty-tc@users.noreply.github.com>
Co-authored-by: Jelle Meeus <sogladev@gmail.com>
Co-authored-by Treeston

This is a partial cherry-pick of: 59db2eeea0

src/server/game/Entities/GameObject/GameObject.cpp

@@ -897,6 +897,7 @@ void GameObject::Update(uint32 diff)
                     return;
                 }
 
+                GetMap()->ApplyDynamicModeRespawnScaling(this, m_respawnDelayTime);
                 m_respawnTime = GameTime::GetGameTime().count() + m_respawnDelayTime;
 
                 // if option not set then object will be saved at grid unload