Make dpctl tensor device hashable, added equality comparison

[oleksandr-pavlyk]

Added dpctl.tensor.Device.__eq__ and dpctl.tensor.Device.__hash__ methods and tests.

import dpctl.tensor as dpt
x = dpt.empty(10)
y = dpt.empty(10)
assert x.device == y.device 

The assertion used to fail, but returns True now.

• Have you provided a meaningful PR description?
• Have you added a test, reproducer or referred to an 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?

[github-actions]

View rendered docs @ https://intelpython.github.io/dpctl/pulls/1048/index.html

[coveralls]

Coverage: 82.097% (+0.02%) from 82.076% when pulling 3dda4f4 on make-dpctl-tensor-Device-hashable into 949711e on master.

[github-actions]

Array API standard conformance tests for dpctl=0.14.1dev1=py310h76be34b_48 ran successfully.
Passed: 33
Failed: 801
Skipped: 280

[github-actions]

Deleted rendered PR docs from intelpython.github.com/dpctl, latest should be updated shortly. 🤞

[github-actions]

Array API standard conformance tests for dpctl=0.14.1dev1=py310h76be34b_50 ran successfully.
Passed: 33
Failed: 801
Skipped: 280