[DRE-maint] Bug#969157: ruby-diaspora-federation-rails: FTBFS with rails 6 - Could not find 'actionpack' (< 6, >= 4.2) - did find: [actionpack-6.0.3.1]

[Pirate Praveen]

Package: ruby-diaspora-federation-rails
Version: 0.2.6-1
Severity: serious
User: pkg-ruby-extras-maintainers at lists.alioth.debian.org
Usertags: rails6-transition

This package fails to build from source with rails 6.

┌──────────────────────────────────────────────────────────────────────────────┐
│ Checking Rubygems dependency resolution on ruby2.7 │
└──────────────────────────────────────────────────────────────────────────────┘

GEM_PATH=/<<PKGBUILDDIR>>/debian/ruby-diaspora-federation-rails/usr/share/rubygems-integration/all:/var/lib/gems/2.7.0:/usr/lib/ruby/gems/2.7.0:/usr/share/rubygems-integration/2.7.0:/usr/share/rubygems-integration/all:/usr/lib/x86_64-linux-gnu/rubygems-integration/2.7.0 
ruby2.7 -e gem\ \"diaspora_federation-rails\"
/usr/lib/ruby/2.7.0/rubygems/dependency.rb:313:in `to_specs': Could not 
find 'actionpack' (< 6, >= 4.2) - did find: [actionpack-6.0.3.1] 
(Gem::MissingSpecVersionError)
Checked in 
'GEM_PATH=/<<PKGBUILDDIR>>/debian/ruby-diaspora-federation-rails/usr/share/rubygems-integration/all:/var/lib/gems/2.7.0:/usr/lib/ruby/gems/2.7.0:/usr/share/rubygems-integration/2.7.0:/usr/share/rubygems-integration/all:/usr/lib/x86_64-linux-gnu/rubygems-integration/2.7.0', 
execute `gem env` for more information
 from /usr/lib/ruby/2.7.0/rubygems/specification.rb:1402:in `block in 
activate_dependencies'
 from /usr/lib/ruby/2.7.0/rubygems/specification.rb:1391:in `each'
 from /usr/lib/ruby/2.7.0/rubygems/specification.rb:1391:in 
`activate_dependencies'
 from /usr/lib/ruby/2.7.0/rubygems/specification.rb:1373:in `activate'
 from /usr/lib/ruby/2.7.0/rubygems/core_ext/kernel_gem.rb:68:in `block 
in gem'
 from /usr/lib/ruby/2.7.0/rubygems/core_ext/kernel_gem.rb:68:in 
`synchronize'
 from /usr/lib/ruby/2.7.0/rubygems/core_ext/kernel_gem.rb:68:in `gem'
 from -e:1:in `<main>'

Full log is 
https://people.debian.org/~praveen/rails6-meta-build/buildlogs/ruby-diaspora-federation-rails.log