[Rails5] `StorageHelper#storage_counter uses commas as thousands separator` fails

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https://gitlab.com/gitlab-org/gitlab-ce/-/jobs/72483405

  18) StorageHelper#storage_counter uses commas as thousands separator
      Failure/Error: expect(helper.storage_counter(100_000_000_000_000_000)).to eq '90,949.5 TB'

        expected: "90,949.5 TB"
             got: "88.8 PB"

        (compared using ==)
      # ./spec/helpers/storage_helper_spec.rb:18:in `block (3 levels) in <top (required)>'