[FIX] Get classifier version in lc_classification_step

[AlxEnashi]

The alerce classifiers repo already has code to get the model version from the model path.
This methos should be called from the step to get the version to store in the db.

• Unittest AlerceClassifiers code to get versoin
• Integration test of the result in the scribe
• Refactor step to get the version from Alerce Classifiers