ci: Re-enable armv5te by fixing flaky tests

They have been disabled by https://github.com/crossbeam-rs/crossbeam/commit/595c9b482fce0daae77fb95b3510ba35bc6b656c.

• macos-latest; https://github.com/crossbeam-rs/crossbeam/pull/1283
  • tick.rs fire https://github.com/crossbeam-rs/crossbeam/actions/runs/27081306869/job/79927597684#step:7:1834
• armv5te
  • golang.rs chan_test::test_select_stress https://github.com/crossbeam-rs/crossbeam/actions/runs/27081306869/job/79927597680#step:8:1467
  • zero.rs mpmc https://github.com/crossbeam-rs/crossbeam/actions/runs/28765352882/job/85288412923