[REQ] [Go] Exclude tests from code generation

Created by: gcatanese

Optionally exclude tests from code generation

In #13559 (closed) the test files are also included in the code generation of the Go client. However, sometimes developers might want to skip those (ie they have already existing test code or want to implement the test cases in a different way)

Solution

Add an additional flag that allows skipping the generation of the test code