Update to metasploit_data_models 0.14.2

## Verification Steps


- [x] ```msfconsole -e test```
- [x] ```irb```
- [x] create a vuln

```ruby
require 'factory_girl'
FactoryGirl.definition_file_paths = [ MetasploitDataModels.root.join('spec', 'factories') ] 
FactoryGirl.find_definitions

v = FactoryGirl.create(:mdm_vuln, :refs => [FactoryGirl.create(:mdm_ref)])
```
- [ ] delete the vuln
```
v.destroy
```
- [x] this should not raise any errors