[main] Correct incorrect connection_idle_timeout setting (#1309)

[kilfoyle]

Backport

This will backport the following commits from 8.15 to main:

• Correct incorrect connection_idle_timeout setting (#1309)

Questions ?

Please refer to the Backport tool documentation

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[mergify]

This pull request does not have a backport label. Could you fix it @kilfoyle? 🙏
To fixup this pull request, you need to add the backport labels for the needed
branches, such as:

• backport-/d./d is the label to automatically backport to the /d./d branch. /d is the digit
  NOTE: backport-skip has been added to this pull request.

[karenzone]

LGTM!