Update log4j to 2.17

[loganaden]

This fixes this security issue: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-45105

[coveralls]

Coverage remained the same at 93.781% when pulling af836be on cyberstormdotmu:master into dabb78c on Netflix:master.

[tgianos]

Thanks @loganaden but looks like by now we should be on 2.17.1 as there is still a vulnerability on 2.17.0. I'll upgrade to that in separate PR.