Add libclang_rt.ubsan_standalone to all debug builds

This is needed to run tests that use `sanitize: { undefined: true }`.

(this is a cherry-pick of fc6f2a43)

Test: run test that needs ubsan on cf_x86_64_phone
      without this change: fails to link
      with this change: works
Bug: 255414852
Merged-In: Id5d3be9bafcc4dbaaf59ca55728ffc40b5cc4af5
Change-Id: Id5d3be9bafcc4dbaaf59ca55728ffc40b5cc4af5