MSP-9531 Zip Workspace imports now working

MSP-9531

## Steps to Verify
### Pro UI
- [ ] Be on pro diablo-ga
- [ ] Generate some data: `rails runner db/runners/generate_dataset.rb --host-count=5`
- [ ] LoadTesting workspace, Exports -> Export Data
- [ ] Generate a Zip Workspace export
- [ ] Once the export is complete, download the file
- [ ] In a new workspace, import the zip file
- [ ] Import should complete without error
- [ ] New workspace should contain data (the host count will match LoadTesting; the exact count of services and vulnerabilities will be lower in the new workspace due to the duplicated nature of some of the generated data)

### CLI
- [ ] `cd pro/engine && ./msfpro`
- [ ] `db_import path/to/zip_workspace_export.zip`
- [ ] Should result in goodness like:
```
[*] Importing 'Metasploit Zip Export' data
[*] Importing 'Metasploit XML' data
[*] Importing host 121.131.70.22
```
- [ ] `hosts` should show data