[DRE-maint] ruby-handlebars-assets is marked for autoremoval from testing

[Debian testing autoremoval watch]

ruby-handlebars-assets 2:0.23.3+dfsg-2 is marked for autoremoval from testing on 2020-03-23

It is affected by these RC bugs:
952026: ruby-handlebars-assets: FTBFS: ERROR: Test "ruby2.5" failed: Invalid gemspec in [handlebars_assets.gemspec]: No such file or directory - git