added new Go project - REST API masterclass

[enkeyz]

Description

Added a new Go project.

Motivation and Context

The Go category doesn't have a similar tutorial.

How Has This Been Tested?

I completed it.

Types of changes

• Content Update (change which fixes an issue or updates an already existing submission)
• New Article (change which adds functionality)
• Documentation change

Checklist:

• My code follows the code style of this project.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have made checks to ensure URLs and other resources are valid

[tuvtran]

Maybe add a video tag?