os/user:nolibgcc: TestGroupIdsTestUser failures [1.24 backport] #74760
Description
@dmitshur requested issue #73523 to be considered for backport to the next 1.24 minor release.
@gopherbot Please backport to Go 1.24. This is a test-only fix to resolve flaky test failures whose frequency increased recently after a different scheduling of parallel test execution. No need for Go 1.23 backport because the test is new to Go 1.24. (CC @mknyszek, @qmuntal.)