adding beginner-friendly notebook on text classification with DistilBERT/TF 
Author: peterbayerle
Pull request: yes

# What does this PR do?
Looking at the current community notebooks, it seems that few are targeted for absolute beginners and even fewer are written with TensorFlow. This notebook describes absolutely everything a beginner would need to know, including how to save/load their model and use it for new predictions (this is often omitted in tutorials)

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## Before submitting
- [ ] This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
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      Pull Request section?
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## Who can review?

Anyone in the community is free to review the PR once the tests have passed. Feel free to tag
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