Adding minimum range to PC2 in collision monitor (backport #5392)

[mergify]

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This is an automatic backport of pull request #5392 done by [Mergify](https://mergify.com).

[mergify]

Cherry-pick of 40a0451 has failed:

On branch mergify/bp/kilted/pr-5392
Your branch is up to date with 'origin/kilted'.

You are currently cherry-picking commit 40a04517.
  (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:   nav2_collision_monitor/include/nav2_collision_monitor/pointcloud.hpp
	modified:   nav2_collision_monitor/test/sources_test.cpp

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   nav2_collision_monitor/src/pointcloud.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]

@mergify[bot], all pull requests must be targeted towards the main development branch.
Once merged into main, it is possible to backport to @kilted, but it must be in main
to have these changes reflected into new distributions.