solves "Chef::Exceptions::ValidationFailed [..] [String]!  You passed :rails_application"

```
================================================================================
Error executing action `run` on resource 'ruby_block[rails_app before_deploy]'
================================================================================


Chef::Exceptions::ValidationFailed
----------------------------------
Option cookbook must be a kind of [String]!  You passed :rails_application.


Cookbook Trace:
---------------
/tmp/chef-solo/cookbooks/rails_application/recipes/default.rb:99:in `block (3 levels) in from_file'
/tmp/chef-solo/cookbooks/rails_application/recipes/default.rb:97:in `block (2 levels) in from_file'
/tmp/chef-solo/cookbooks/application/libraries/default.rb:187:in `safe_recipe_eval'
/tmp/chef-solo/cookbooks/application/libraries/default.rb:163:in `callback'
/tmp/chef-solo/cookbooks/application/providers/default.rb:112:in `block (2 levels) in before_deploy'


Resource Declaration:
---------------------
# In /tmp/chef-solo/cookbooks/application/providers/default.rb

107:   ruby_block "#{new_resource.name} before_deploy" do
108:     block do
109:       new_resource.sub_resources.each do |resource|
110:         resource.run_action :before_deploy
111:       end
112:       callback(:before_deploy, new_resource.before_deploy)
113:     end
114:   end
115: end



Compiled Resource:
------------------
# Declared in /tmp/chef-solo/cookbooks/application/providers/default.rb:107:in `before_deploy'

ruby_block("rails_app before_deploy") do
  action "run"
  retries 0
  retry_delay 2
  block_name "rails_app before_deploy"
  cookbook_name :rails_application
  block #<Proc:0xa348898@/tmp/chef-solo/cookbooks/application/providers/default.rb:108>
end
```