Fix: Rubocop offences

Author: dalpo

lib/rails_admin/config/fields/types/bson_object_id.rb

@@ -1,8 +1,8 @@
 require 'rails_admin/config/fields/types/string'
 begin
-  require 'mongoid' rescue nil
-rescue Exception => e
-  # puts "[RailsAdmin] #{e.message}"
+  require 'mongoid'
+rescue LoadError => e
+  puts "[RailsAdmin] #{e.message}"
 end
 
 module RailsAdmin