This is an NFC change for the suffix tree.
We use MachineOutliner to reduce our binary size recently, so I just look into the code of the suffix tree.
But I think it is hard to debug, so I use this NFC change to enhance this.
The log just like:
Node[Root#0]: StartIdx=4294967295, EndIdx=4294967295, Childrens = [3,2,1,] Node[Leaf#1]: StartIdx=2, EndIdx=5, Childrens =  Node[Leaf#2]: StartIdx=0, EndIdx=5, Childrens =  Node[Leaf#3]: StartIdx=1, EndIdx=5, Childrens = 
BTW, I found the suffix tree does not have a default terminator in the array.