Fix flaky quick action specs due to ordering

What does this MR do and why?

The quick action user extractor does not return users in a deterministic order so the success message does not necessarily follow the same order of users given by the user

Resolves gitlab-org/release/tasks#6678 (closed)

This is similar to !129053 (merged) / gitlab-org/quality/engineering-productivity/master-broken-incidents#3261 (closed)

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