Update score when found old scores for find_or_insert APIs

[jiashuy]

To priority those latest accessed keys, we should update the score when found them in API find_or_insert. Including APIs:

• find_or_insert(at least 3 kernels)
• find_or_insert_ptr(at least 1 kernel). We don't need to update the score for API find, because API find usually used with insert_and_evict, the later API will update the score for keys found previous.