[SYCL] Deprecate removed extension leftover (#22320)
In favor of existing SYCL2020 objects.
And update E2E tests to use standard SYCL2020 objects.
I believe these objects were introduced in
https://github.com/intel/llvm/blob/sycl/sycl/doc/extensions/removed/sycl_ext_oneapi_group_algorithms.asciidoc
