fix azure snapshots
I've a feeling that we stopped creating them as cron is unhappy day by day:
/usr/local/lib/ruby/gems/2.3.0/gems/bundler-1.14.6/lib/bundler/spec_set.rb:87:in `block in materialize': Could not find concurrent-ruby-1.0.2 in any of the sources (Bundler::GemNotFound)
from /usr/local/lib/ruby/gems/2.3.0/gems/bundler-1.14.6/lib/bundler/spec_set.rb:80:in `map!'
from /usr/local/lib/ruby/gems/2.3.0/gems/bundler-1.14.6/lib/bundler/spec_set.rb:80:in `materialize'
from /usr/local/lib/ruby/gems/2.3.0/gems/bundler-1.14.6/lib/bundler/definition.rb:176:in `specs'
from /usr/local/lib/ruby/gems/2.3.0/gems/bundler-1.14.6/lib/bundler/definition.rb:235:in `specs_for'
from /usr/local/lib/ruby/gems/2.3.0/gems/bundler-1.14.6/lib/bundler/definition.rb:224:in `requested_specs'
from /usr/local/lib/ruby/gems/2.3.0/gems/bundler-1.14.6/lib/bundler/runtime.rb:118:in `block in definition_method'
from /usr/local/lib/ruby/gems/2.3.0/gems/bundler-1.14.6/lib/bundler/runtime.rb:19:in `setup'
from /usr/local/lib/ruby/gems/2.3.0/gems/bundler-1.14.6/lib/bundler.rb:100:in `setup'
from /usr/local/lib/ruby/gems/2.3.0/gems/bundler-1.14.6/lib/bundler/setup.rb:20:in `<top (required)>'
from /usr/lib/ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
from /usr/lib/ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
This issue is to track the investigation.