[Streaming]Fix potential memory problems when delete buffer. (#21101)
[Streaming]Fix potential memory problems when delete buffer. (#21101)

`delete buffer` -> `delete[] buffer` to fix potential memory problems under C++14, such as jemalloc deadlock.
ray-project/ray,ray-project/ray,ray-project/ray,ray-project/ray,ray-project/ray,ray-project/ray,ray-project/ray,ray-project/ray