Replace Rubinius (no longer tested in CI) with TruffleRuby (nowadays tested in CI)
Replace Rubinius (no longer tested in CI) with TruffleRuby (nowadays tested in CI)

Co-authored-by: Josef Šimánek <613ee6e0f24b58682860bdd8da9dccf38b01e3da@gmail.com>

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