[DRE-maint] Bug#918391: ruby-spring FTBFS with rails 5.2.0

[Adrian Bunk]

Source: ruby-spring
Version: 1.3.6-2
Severity: serious
Tags: ftbfs buster sid

https://tests.reproducible-builds.org/debian/rb-pkg/unstable/amd64/ruby-spring.html

...
/usr/lib/ruby/vendor_ruby/bundler/resolver.rb:289:in `block in verify_gemfile_dependencies_are_found!': Could not find gem 'activesupport (~> 4.2.0)' in any of the gem sources listed in your Gemfile. (Bundler::GemNotFound)
...