Added ASAN tesing in commit process, used clang-8 for
ASAN build under debian-buster image. Added for testing
only the passing test suites, the rest of the tests
not used and will be enabled durring issue #4360. Also
fixed job for testing LTO with clang on debian-buster
in travis-ci, changed it to the same as in gitlab-ci,
changed default clang to clang-8.

Closes #4359