Added phpunit setup to infrastructure.

Some code style fixes.

- creating ASYST API on Flask server
- preparation a query to API
- response processing and Manual Grading Form manipulations (not yet covers slots !!!).

Added Plugin DB Migration.
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TODO: Create an API to use script run_LR_SBERT.py on http://127.0.0.1:5000/api/data or like that.

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TODO: Create an API to use script run_LR_SBERT.py on http://127.0.0.1:5000/api/data or like that. Configure relative paths at ASYST script (run_LR_SBERT.py).

All necessary input data are provided.
Python ASYST script (run_LR_SBERT.py) is set with absolute paths.
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Result:
On script execution we obtain just once the result at /var/www/html/moodle/asyst/Source/Skript/outputs/test.tsv
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TODO: Create an API to use script run_LR_SBERT.py on http://127.0.0.1:5000/api/data or like that. Configure relative paths at ASYST script (run_LR_SBERT.py).