[21921] Sign the generated code with the Fast DDS-Gen version (backport #458)

[mergify]

Description

This PR adds the Version of Fast DDS-Gen to the generated code.

@Mergifyio backport 4.0.x 3.3.x 2.5.x 2.1.x

Contributor Checklist

• Commit messages follow the project guidelines.

• N/A 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 New feature has been documented/Current behavior is correctly described in the documentation.

• 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.

---

This is an automatic backport of pull request #458 done by [Mergify](https://mergify.com).