Make debugging option project-agnostic

[nguyenmthien]

Description
One important feature of an example project is that it should stay true regardless of system settings, and project design. A good project template should minimize the user's interaction and flatten the learning curve as much as possible. While this project has a good potential, some corners need to be ironed out. This issue focuses on the debugging aspect of this example.

Expected behavior
The .vscode folder should be portable. This means one can copy this .vscode folder to another west-compatible project and expects the debugging feature to work.

Actual behavior
This will lead to an error in vscode due to hard-coding of the MCU and runner name to the launch.json file