Add dpctl.SyclQueue.memset() method

[vlad-perevezentsev]

This PR proposes adding dpctl.SyclQueue.memset and dpctl.SyclQueue.memset_async methods as a Python wrapper over sycl::queue::memset backed by the existing DPCTLQueue_Memset and a new DPCTLQueue_MemsetWithEvents C-API function and adding a new test_sycl_queue_memset.py

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[github-actions]

View rendered docs @ https://intelpython.github.io/dpctl/pulls/2361/index.html

[vlad-perevezentsev]

@ndgrigorian I implemented cpdef memset without validating val, i.e. matching sycl::queue::memset semantics where the value is silently truncated toits least significant byte.
Does it make sense to explicitly validate that val is within [0, 255]?

[coveralls]

Coverage is 74.51% — add_sycl_queue_memset into master. No base build found for master.

[antonwolfy]

The docstring promises val is interpreted as unsigned char (LSB only), but nothing verifies e.g. memset(mem, 0x1FF) fills 0xFF or -1 fills 0xFF. There is no error case to test here (values truncate, not reject).

[vlad-perevezentsev]

This case is already covered by test_memset_value_truncated_to_byte (negatives and overflow)
https://github.com/IntelPython/dpctl/pull/2361/changes#diff-8cf72656d339e0f446c2227869696dee611bdce0bc37434f62419482dc4cd075R192

[ndgrigorian]

LGTM, thank you @vlad-perevezentsev