UCM/ZE/TEST: Add ZE support to gtest mem_buffer and UCM hook tests (#11321)

* UCM/ZE/TEST: Add ZE support to mem_buffer and UCM hook tests

- Extend gtest mem_buffer with ZE host, device, and managed
  allocators, including ZE copy and memset paths, and centralize
  ZE runtime initialization.
- Add UCM ZE hook tests to validate alloc and free callbacks.
- Update gtest Makefile.am to include ZE sources and linker flags.

* UCM/ZE/TEST: fix format

* UCM/ZE/TEST: Clean up ZE test code

Remove the dead HAVE_ZE guard around ZE memset case labels because
the enum values are always defined. Use UCS_TEST_ABORT instead of
UCS_TEST_SKIP in ZE allocate() paths for consistency with memset and
copy_between handling. Also drop the duplicate -lze_loader from
gtest_LDADD since it is already included in ZE_LIBS.

Signed-off-by: Yaser Afshar <yaser.afshar@intel.com>

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Signed-off-by: Yaser Afshar <yaser.afshar@intel.com>