[Enhancement] ToString representation of minds object

[Better-Boy]

Short description of current behavior

Currently, Mind object doesn't have a string representation of it's variable value when the object is printed. Instead the object address is printed.

Steps 🕵️‍♂️ 🕵️‍♀️

• Add a tostring representation of the Mind object where the object variable values are printed.
• print(mind_obj), str(mind_obj) or just entering the mind_obj in python console should print the object variable values.

📢 Additional rewards 🏆

This issue brings 5️⃣ 0️⃣ points for SWAG and entry into the draw for a 👇 :

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[ZoranPandovski]

@Better-Boy Note that the issue points are rewarded by the MindsDB team, not by the contributor