Fix gh-1539

[npolina4]

closes #1539 dpnp.sum(x, axis=0) is very slow on integral 64-bit types

call dpctl.tensor.sum() function for 64-bit types

• Have you provided a meaningful PR description?
• Have you added a test, reproducer or referred to issue with a reproducer?
• Have you tested your changes locally for CPU and GPU devices?
• Have you made sure that new changes do not introduce compiler warnings?
• Have you checked performance impact of proposed changes?

[github-actions]

View rendered docs @ https://intelpython.github.io/dpnp/index.html

[vlad-perevezentsev]

LGTM!
thanks @npolina4