Flaky test spec/features/groups/members/manage_members_spec.rb[1:5:2:5]

Job #3309524262 failed for 6f7573fd:

It was failing with:

Failures:
  1) Groups > Members > Manage members when inviting behaves like inviting members invites user by username and invites user by email
     Got 0 failures and 2 other errors:
     Shared Example Group: "inviting members" called from ./spec/features/groups/members/manage_members_spec.rb:87
     1.1) Failure/Error: super
          Capybara::ElementNotFound:
            Unable to find visible css "tbody > tr" with text "Mary Jane" within #<Capybara::Node::Element tag="table" path="/HTML/BODY[1]/DIV[3]/DIV[1]/DIV[3]/MAIN[1]/DIV[2]/DIV[1]/DIV[2]/DIV[2]/DIV[1]/DIV[1]/DIV[2]/TABLE[1]">
            Timeout (30s) reached while running a waiting Capybara finder.
            Consider using a non-waiting finder.
            See https://www.cloudbees.com/blog/faster-rails-tests
          # ./spec/support/capybara_slow_finder.rb:18:in `synchronize'
          # ./spec/support/helpers/features/members_helpers.rb:32:in `block in find_row'
          # ./spec/support/helpers/features/members_helpers.rb:31:in `find_row'
          # ./spec/support/helpers/features/members_helpers.rb:37:in `find_member_row'
          # ./spec/support/shared_examples/features/inviting_members_shared_examples.rb:67:in `block (2 levels) in <main>'

This is in a different test than #382373 (closed) but the cause might be the same.