TST: fix compatibility with numpy 2 (copy semantics) in a coordinates test

[neutrinoceros]

Description

Follow up to #16166
I missed this test in my previous PRs because I didn't have jplephem installed. This was caught in today's daily cron.

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[github-actions]

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[mhvk]

Well, if that's all you missed - pretty good! Let's get it in.

[neutrinoceros]

@mhvk I don't see a backport PR for this. Can you ping the bot here ? (I assume I don't have rights to do it myself)

[mhvk]

@meeseeksdev backport to 6.0.x

[lumberbot-app]

Something went wrong ... Please have a look at my logs.

It seems that the branch you are trying to backport to does not exist.

[mhvk]

@meeseeksdev backport to 6.1.x

[lumberbot-app]

Something went wrong ... Please have a look at my logs.

It seems that the branch you are trying to backport to does not exist.

[mhvk]

I think I forgot the incantation... Of course, the real problem is that I forgot to set the label...

[mhvk]

@meeseeksdev backport to v6.1.x

[mhvk]

Arrgghh, just forgot a "v". But now it is done at least.

[neutrinoceros]

Thank you !