Add Host scope to login

MSP-10856

- [x] VERIFY specs pass
- [x] VERIFY by_host_id scope on Metasploit::Credential::Login

## Post-merge steps
- [x] Edit `lib/metasploit/credential/version.rb` and increment the PATCH constant
- [ ] Verify that 'rake spec' passes all specs
- [ ] Commit and push
- [ ] Create the appropriate tag
- [ ] Push the tag