[16315] Doxygen documentation: add deprecation notice to ThroughputControllerDescriptor (backport #3165)

[mergify]

This is an automatic backport of pull request #3165 done by Mergify.
Cherry-pick of d34a076 has failed:

On branch mergify/bp/2.6.x/pr-3165
Your branch is up to date with 'origin/2.6.x'.

You are currently cherry-picking commit d34a07640.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   include/fastdds/dds/publisher/qos/DataWriterQos.hpp
	modified:   include/fastdds/rtps/attributes/WriterAttributes.h
	modified:   include/fastdds/rtps/flowcontrol/ThroughputControllerDescriptor.h

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   include/fastdds/dds/core/policy/QosPolicies.hpp
	both modified:   include/fastdds/rtps/attributes/RTPSParticipantAttributes.h

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

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[JLBuenoLopez]

LGTM