fix: model reported as unknown when present but hash not yet calculated.

[prodigy]

Description

I wanted to create a new worker and copied the extensions configuration. When enabling the new worker it always reported ERROR: Unknown model for all the models.

I found out that the sd web ui had not yet calculated all the hashes as it was a completely new and empty instance. No models except the default had been loaded. This change forces the models to have their sha hash calculated when being loaded as part of a horde job.

Type of changes

• [x] Bugfix
• [ ] Feature
• [ ] Refactoring
• [ ] Optimization
• [ ] Documentation
• [ ] CI/CD
• [ ] Other

Please check the following items before submitting your pull request

• [x] I've checked that this isn't a duplicate pull request.
• [x] I've tested my changes with the latest SD-Webui version.
• [x] I've format my code with black: black .
• [x] I've lint my code with flake8: flake8 .
• [x] I've read the Contribution Guidelines
• [x] I've read the Code of Conduct