Backport PR #16391 on branch v6.1.x (Fix endian-dependence of test introduced in gh-16380) - #16397

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Weird failures... gonna close/reopen and see.

aarch64 timed out but the others passed, so probably good enough for a backport PR. 🤷‍♀️

These timeouts have been consistent for a little while now, so I don't think it's related (but I have no idea what's causing them).