All tests don't include KerasModel

[gsolard]

Problem

Some tests (such as those of ModelAggregation) don't include all types of models (for example ModelKeras). They should in order to be more robust

Concerned template

• [x] NLP template
• [x] NUM template
• [ ] VISION template
• [ ] API template
• [ ] How templates are generated - Jinja

Solution

Audit all tests and add some more varying the types of models (pipeline, Keras, huggingface, ...)