Fix CMake error in OS compiler workflow

[ndgrigorian]

This PR fixes the failing OS compiler workflow, which has been throwing a CMake error

OS compiler versioning output changed, so the Clang version is preceded by another string giving the date and specifying the compiler is the SYCL nightly compiler

This PR modifies dpctl CMake to check if the "Intel SYCL Compiler Nightly" string is in the version string. If so, the next member of the list, containing the Clang version, is used instead

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[github-actions]

View rendered docs @ https://intelpython.github.io/dpctl/pulls/2211/index.html

[coveralls]

coverage: 86.269%. remained the same
when pulling bed074b on fix-intel-sycl-compiler-cmake-os-ci
into c5c82b4 on master.

[github-actions]

Array API standard conformance tests for dpctl=0.22.0dev0=py310h93fe807_88 ran successfully.
Passed: 1115
Failed: 43
Skipped: 82

[github-actions]

Array API standard conformance tests for dpctl=0.22.0dev0=py310h93fe807_88 ran successfully.
Passed: 1115
Failed: 43
Skipped: 82

[github-actions]

Array API standard conformance tests for dpctl=0.22.0dev0=py310h93fe807_88 ran successfully.
Passed: 1114
Failed: 44
Skipped: 82

[antonwolfy]

Would it make sense to update the libsyclinterface/cmake/modules/FindIntelSyclCompiler.cmake with the latest content from the recent 2025.3 release instead?