Fix GAP messages are not sent when there is no Reader requesting the DATA (backport #6181)

[mergify]

Description

When Content Filter is being performed on the writer side, and samples are always irrelevant for all readers, currently a heartbeat period is received without notification of the previous GAP sequence of samples, and the readers annotate those samples as lost. This PR fixes this, ensuring that a GAP message is sent before the HEARTBEAT period or before a DATA for one of the readers.

@Mergifyio backport 3.3.x 3.2.x 2.14.x

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

• Any new/modified methods have been properly documented using Doxygen.

• N/A: Any new configuration API has an equivalent XML API (with the corresponding XSD extension)

• Changes are backport compatible: they do NOT break ABI nor change library core behavior.

• Changes are API compatible.

• N/A: New feature has been added to the versions.md file (if applicable).

• 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.
• N/A: If this is a critical bug fix, backports to the critical-only supported branches have been requested.
• 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 #6181 done by [Mergify](https://mergify.com).

[mergify]

Cherry-pick of 062258c has failed:

On branch mergify/bp/2.14.x/pr-6181
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  (fix conflicts and run "git cherry-pick --continue")
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Changes to be committed:
	modified:   .github/workflows/reusable-sanitizers-ci.yml
	modified:   include/fastdds/rtps/writer/ReaderProxy.h
	modified:   include/fastdds/rtps/writer/StatefulWriter.h
	modified:   src/cpp/rtps/writer/ReaderProxy.cpp

Unmerged paths:
  (use "git add/rm <file>..." as appropriate to mark resolution)
	deleted by us:   examples/cpp/content_filter/SubscriberApp.hpp
	both modified:   src/cpp/rtps/writer/StatefulWriter.cpp
	both modified:   test/blackbox/common/DDSBlackboxTestsContentFilter.cpp
	deleted by us:   test/dds/xtypes/TypeLookupServiceSubscriber.cpp

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

[mergify]

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[MiguelCompany]

@Mergifyio rebase

[mergify]

rebase

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