Weapon entity index
Returns if the weapon is in burst mode.
Only the Glock and Famas can return 1 as they are the only guns in the game that have a burst fire mode.
This native does not check that the provided entity is actually a weapon entity. It will return incorrect values for non-weapon entities.
1 if the weapon is in burst mode, 0 otherwise
If an invalid entity index or a client index is provided, an error will be thrown.