Backport PR #20199 on branch v8.0.x (CI: upgrade weekly cron devdeps jobs to Python 3.14) - #20201

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Hmm...

ValueError: option dest 'remote_data' already used by ['-R'] (this is the option that maps to dest 'remote_data'); pass dest='remote_data' explicitly to share the destination

@neutrinoceros how did you fix this on main?

Now part of #20204