[19175] Ubuntu example testing automation infrastrucure

[EduPonz]

Description

This PR adds infrastructure to enable automated example testing using CTest. The approach consists on using docker compose to run the example executables (publisher and subscriber) both in different and same container instances, capturing the output to verify the correct functioning of the example in question. To launch the different compose commands and perform the validation, a python script within the pytest framework is used, and the pytest command is added as a CTest test in CMake. To enable the example testing, this PR also adds a new CMake option FASTDDS_EXAMPLE_TESTS which defaults to OFF.

With this infrastructure, adding new tests consists on simply adding the corresponding compose file and testing/verification function. It is important to note that even when the infrastructure is semi-prepared to support example testing in Windows, the only support that this PR provides is for Ubuntu, as some details regarding the Windows docker images are out of scope for now.

This PR depends on:

• [17513] Add nightly Ubuntu Github CI #4109

TODO:

• Drop the commit DROP: changes for testing

Contributor Checklist

• Commit messages follow the project guidelines.
• The code follows the style guidelines of this project.
• Tests that thoroughly check the new feature have been added/Regression tests checking the bug and its fix have been added; the added tests pass locally
• N/A: Any new/modified methods have been properly documented using Doxygen.
• N/A: Changes are ABI compatible.
• N/A: Changes are API compatible.
• N/A: New feature has been added to the versions.md file (if applicable).
• New feature has been documented/Current behavior is correctly described in the documentation. Documentation PR:
  • [19175] Documentation of FASTDDS_EXAMPLE_TESTS CMake option Fast-DDS-docs#697
• N/A: Applicable backports have been included in the description.

Reviewer Checklist

• The PR has a milestone assigned.
• The title and description correctly express the PR's purpose.
• Check contributor checklist is correct.
• Check CI results: changes do not issue any warning.
• Check CI results: failing tests are unrelated with the changes.

[EduPonz]

CI passed here