adding API change for spin_until_complete (backport #3328)

[mergify]

This is an automatic backport of pull request #3328 done by Mergify.
Cherry-pick of fd9adb8 has failed:

On branch mergify/bp/foxy/pr-3328
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Changes to be committed:
	modified:   source/Releases/Release-Iron-Irwini.rst
	modified:   source/The-ROS2-Project/Contributing/Migration-Guide-Python.rst
	modified:   source/Tutorials/Beginner-Client-Libraries/Writing-A-Simple-Cpp-Service-And-Client.rst
	modified:   source/Tutorials/Beginner-Client-Libraries/Writing-A-Simple-Py-Service-And-Client.rst
	modified:   source/Tutorials/Intermediate/Writing-an-Action-Server-Client/scripts/client_0.py

Unmerged paths:
  (use "git add/rm <file>..." as appropriate to mark resolution)
	deleted by us:   source/Tutorials/Advanced/FastDDS-Configuration.rst
	both modified:   source/Tutorials/Beginner-Client-Libraries/Custom-ROS2-Interfaces.rst

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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