LAB 02 : Add note for VSCode trust and fix two variable errors in C# and Python code

[massimobonanni]

Module: 02

Lab/Demo: 02

Fixes #41

Changes proposed in this pull request:

• I added a note regarding the pop-up that visual studio code shows to confirm the trust of the newly cloned code
• In the C# and Python code reported in the instructions, the name of the variable containing the name of the model to be used is incorrect. I corrected the name. (Fixed Issue #41 )

[massimobonanni]

I add another pull-request with the same fixes plus others