Condition test exercising fp16 support on availability of HW support

[oleksandr-pavlyk]

This PR modifies the test which unconditionally exercises operations on arrays with float16 data-type.
The test fails on HW without float16 native support.

This PR make test only do that if HW has aspect fp16. Test also adds step to unconditionally use float32
to maintain coverage level on all platforms.

• 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/974/index.html

[coveralls]

Coverage remained the same at 81.996% when pulling d859362 on fix-test-run-on-hw-without-fp16-support into 2c86ef6 on master.

[github-actions]

Array API standard conformance tests for dpctl=0.14.0dev1=py310h8c27c75_21 ran successfully.
Passed: 33
Failed: 801
Skipped: 3138

[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=0.14.0dev1=py310h8c27c75_21 ran successfully.
Passed: 33
Failed: 801
Skipped: 3138