[DRE-maint] ruby-task-list is marked for autoremoval from testing

[Debian testing autoremoval watch]

ruby-task-list 2.0.0-2 is marked for autoremoval from testing on 2018-04-13

It (build-)depends on packages with these RC bugs:
891755: ruby-html-pipeline: ruby-html-pipeline FTBFS with ruby 2.5: test failures
893610: ruby-sanitize: CVE-2018-3740