[DRE-maint] Bug#870751: ruby-gitlab-flowdock-git-hook FTBFS with ruby-mime-types 3.1-1

[Adrian Bunk]

Source: ruby-gitlab-flowdock-git-hook
Version: 1.0.1-2
Severity: serious
Tags: buster sid

https://tests.reproducible-builds.org/debian/rb-pkg/unstable/amd64/ruby-gitlab-flowdock-git-hook.html

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GEM_PATH=debian/ruby-gitlab-flowdock-git-hook/usr/share/rubygems-integration/all:/var/lib/gems/2.3.0:/usr/lib/x86_64-linux-gnu/rubygems-integration/2.3.0:/usr/share/rubygems-integration/2.3.0:/usr/share/rubygems-integration/all ruby2.3 -e gem\ \"gitlab-flowdock-git-hook\"
/usr/lib/ruby/2.3.0/rubygems/dependency.rb:319:in `to_specs': Could not find 'mime-types' (~> 2.6) - did find: [mime-types-3.1] (Gem::LoadError)
Checked in 'GEM_PATH=debian/ruby-gitlab-flowdock-git-hook/usr/share/rubygems-integration/all:/var/lib/gems/2.3.0:/usr/lib/x86_64-linux-gnu/rubygems-integration/2.3.0:/usr/share/rubygems-integration/2.3.0:/usr/share/rubygems-integration/all', execute `gem env` for more information
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