Integrate Clang AddressSanitizer in tests

[3manifold]

Tested: temporarily introduced a memory leak in an operator to check that asan works:
https://github.com/OpenNMT/CTranslate2/actions/runs/16419223767/job/46392885237#logs

resolves #1928

[jordimas]

For context:

sanitizers (Archived)

This project has been archived and is no longer actively maintained.

The Sanitizers project, which includes AddressSanitizer, MemorySanitizer, ThreadSanitizer, LeakSanitizer, 
and more, is now archived. 

[3manifold]

For context:

sanitizers (Archived)

This project has been archived and is no longer actively maintained.

The Sanitizers project, which includes AddressSanitizer, MemorySanitizer, ThreadSanitizer, LeakSanitizer, 
and more, is now archived. 

Thanks for the note. Worth noting that sanitisers still exist but are maintained under the LLVM project (link). I can attempt later to re-run them under the LLVM ecosystem (using clang compiler etc. ). I updated the PR using clang this time.

[3manifold]

@jordimas It seems that the address sanitiser detected an issue in one of the latest project changes ( see #1968 ). Apart from that, all comments were resolved.