Fix a bug where msfconsole -n was broken

Land #3578 first.

MSP-10905

#### Verification
 - [ ] `sudo service postgresql stop`
 - [ ] `RAILS_ENV=production msfconsole -n`
 - [ ] **VERIFY** msfconsole starts without errors. (The warning that the database is disabled is OK)
 - [ ] `mv ~/.msf4/database.yml ~/`
 - [ ] put bogus info in ~/.msf4/database.yml
 - [ ] `msfconsole -y ~/database.yml`
 - [ ] **VERIFY** msfconsole starts with no errors
 - [ ] `db_status`
 - [ ] **VERIFY** connected as expected
 - [ ] `mv ~/database.yml ~/.msf4/`