tests/docker: add sanitizers back to clang build

Fedora23 is but a distant twinkle. The sanitizer works again, and even
if not, we have --enable-sanitizers now.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20190912014442.5757-1-jsnow@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
1 file changed