Export string sets in monitoring infos. (#31838)

[robertwb]

This is a cherry pick of #31838

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[jrmccluskey]

LGTM, waiting on tests to pass

[github-actions]

Checks are failing. Will not request review until checks are succeeding. If you'd like to override that behavior, comment assign set of reviewers

[jrmccluskey]

@robertwb is this precommit failure expected? The same failure happened on your original PR, but it looks like master is green afterwards

[jrmccluskey]

nevermind, the 6th run seems to have passed. strange flake