Transform behaviour+documentation

[djdameln]

📝 Description

• This PR implements a minor change to the transforms workflow. When only a train_transform (and not an eval_transform) is passed to the datamodule, Anomalib will now use the default model-specific transform as the eval transform. Previously it would re-use the train_transform to prevent shape mismatch. We now also raise a warning to urge the user to check their transform configs if only a train_transform or eval_transform is provided. The new behaviour may be a bit less confusing to users.
• Adds documentation for the transform functionality
• Updates the data configs, which still defined some depreceted arguments (this was a leftover from v0.x)

Fixes

#2020

Select what type of change your PR is:

• 🐞 Bug fix (non-breaking change which fixes an issue)
• 🔨 Refactor (non-breaking change which refactors the code base)
• 🚀 New feature (non-breaking change which adds functionality)
• 💥 Breaking change (fix or feature that would cause existing functionality to not work as expected)
• 📚 Documentation update
• 🔒 Security update

✅ Checklist

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• 📋 I have summarized my changes in the CHANGELOG and followed the guidelines for my type of change (skip for minor changes, documentation updates, and test enhancements).
• 📚 I have made the necessary updates to the documentation (if applicable).
• 🧪 I have written tests that support my changes and prove that my fix is effective or my feature works (if applicable).

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[ashwinvaidya17]

Thanks for the efforts! I have one minor comment