Attempts to print a stacktrace on segfault in our integration tests (backport #2776)

[mergify]

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🎉 New feature

Closes #

Depends on: gazebo-tooling/action-gz-ci#81

Summary

Our integration tests often segfault in CI leaving us clueless as to whats happening. This commit is an attempt to vendor backward-cpp and at the same time allows us to get a stacktrace of our segfaulting tests in CI. The current status of this PR is draft.

Other options considered:

We vendor backward-cpp in gz-launch and in gz-utils. Sadly the ubuntu package is not very useful as no cmake targets are provided. I could try to vendor it in gz-cmake or write a bespoke FindBackward package. However, our goal is to use it in tests. This is a very specific use case and I feel maybe the simplest option is to vendor it here and link it against the tests. That way we do not introduce more dependencies via 3rd party package managers and the user has no need to have anything else installed.

Test it

This commit has an example of a test I purposely introduced a segfault in. You can take a look at the github runners and see the stacktrace, Unfortunately, for Jenkins, there may need to be some minor changes on the buildfarm side. In particular we need to install libdwarf-dev, libdw-dev and binutils-dev. We will also need to build with RelWithDebInfo.

Checklist

• Signed all commits for DCO
• Added tests
• Added example and/or tutorial
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
• While waiting for a review on your PR, please help review another open pull request to support the maintainers

Note to maintainers: Remember to use Squash-Merge and edit the commit message to match the pull request summary while retaining Signed-off-by messages.

---

This is an automatic backport of pull request #2776 done by [Mergify](https://mergify.com).

[mergify]

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On branch mergify/bp/ign-gazebo6/pr-2776
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  (fix conflicts and run "git cherry-pick --continue")
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Changes to be committed:
	modified:   CMakeLists.txt
	new file:   test/backward_vendor/backward-cpp/BackwardConfig.cmake
	new file:   test/backward_vendor/backward-cpp/CMakeLists.txt
	new file:   test/backward_vendor/backward-cpp/LICENSE.txt
	new file:   test/backward_vendor/backward-cpp/backward.cpp
	new file:   test/backward_vendor/backward-cpp/backward.hpp

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   .github/workflows/ci.yml
	both modified:   test/CMakeLists.txt

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