Ohai resource: reloading a specific plugin which is marked as "optional" is ignored

Description

Running the example from https://docs.chef.io/resource_ohai.html fails with chef-client >= 14.

Chef Version

Tested with 15.2.20 and 14.13.11

Platform Version

Ubuntu 18.04

Replication Case

Create a cookbook with a recipe containing the example code from the ohai resource. On the first run, when the new user is actually created, the ruby code block fails. With 13.12.14 the code runs without error.

Client Output

  * ruby_block[just an example] action run[2019-08-22T10:41:48+00:00] INFO: Processing ruby_block[just an example] action run (xion_prometheus::test line 13)


    ================================================================================
    Error executing action `run` on resource 'ruby_block[just an example]'
    ================================================================================

    NoMethodError
    -------------
    undefined method `[]' for nil:NilClass

    Cookbook Trace:
    ---------------
    /var/chef/cache/cookbooks/tests/recipes/test.rb:16:in `block (2 levels) in from_file'

    Resource Declaration:
    ---------------------
    # In /var/chef/cache/cookbooks/tests/recipes/test.rb

     13: ruby_block 'just an example' do
     14:   block do                                                                                                                                                                
     15:     # These variables will now have the new values
     16:     puts node['etc']['passwd']['daemonuser']['uid']                                                                                                 
     17:     puts node['etc']['passwd']['daemonuser']['gid']
     18:   end
     19: end                                                                        
                                                                          
    Compiled Resource:                                                              
    ------------------
    # Declared in /var/chef/cache/cookbooks/tests/recipes/test.rb:13:in `from_file'
                 
    ruby_block("just an example") do      
      action [:run]
      default_guard_interpreter :default
      declared_type :ruby_block
      cookbook_name "tests"                                                              
      recipe_name "test"
      block #<Proc:0x0000000004c08448@/var/chef/cache/cookbooks/tests/recipes/test.rb:14>
      block_name "just an example"
    end                                                           

    System Info:                        
    ------------
    chef_version=15.2.20                                   
    platform=ubuntu                                                                                                                                          
    platform_version=18.04                                  
    ruby=ruby 2.6.3p62 (2019-04-16 revision 67580) [x86_64-linux]
    program_name=/usr/bin/chef-client                                               
    executable=/opt/chef/bin/chef-client