chapters/software-stack: Move generated tests at the same level as the source code

[teodutu]

Prerequisite Checklist

• [x] Read the contribution guidelines regarding submitting new changes to the project;
• [x] Tested your changes against relevant architectures and platforms;
• [x] Updated relevant documentation (if needed).

Description of changes

Move support/src/tests/ to support/tests/ so the support/ folder matches the solution/.