[21649] Correct iterator increment after erasing elements in connected_servers_list (backport #5226)

[mergify]

Description

This PR addresses a critical issue with iterator handling in the loop that processes elements of connected_servers_. The original implementation encountered an assertion failure due to invalid iterator increments after removing elements from the container.

Comment for the reviewer:

• Alternative approach to fix the problem: Given that the connected_servers_ list is expected to contain at most one element with the matching guidPrefix, another viable solution could be to use a break statement within the if (it->guidPrefix == pdata->m_guid.guidPrefix) condition. This would immediately exit the loop after finding and removing the element, eliminating the need to handle iterator invalidation explicitly.

@Mergifyio backport 2.14.x 2.10.x

Contributor Checklist

• Commit messages follow the project guidelines.

• The code follows the style guidelines of this project.

• NO: 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

  • The team decided internally to add regression test in a follow-up PR

• N/A: 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.

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This is an automatic backport of pull request #5226 done by [Mergify](https://mergify.com).

[mergify]

Cherry-pick of d4d8e54 has failed:

On branch mergify/bp/2.10.x/pr-5226
Your branch is up to date with 'origin/2.10.x'.

You are currently cherry-picking commit d4d8e5489.
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  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Unmerged paths:
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	both modified:   src/cpp/rtps/builtin/discovery/participant/PDPClient.cpp

no changes added to commit (use "git add" and/or "git commit -a")

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

[MiguelCompany]

This backport is not necessary, since we are not erasing elements.