Finalizing changelog for v6.1.0 - #16381

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close/reopen to make CI happy

Hopefully RTD status would turn green when the job passes. The red X is from a previously cancelled run.

@meeseeksdev backport to main

Wonder why this didn't happen automatically. @pllim - any ideas?

Not sure... Might be a safeguard because technically "backport to main" does not make sense. I can ask upstream.

• backport-main label does not auto backport scientific-python/MeeseeksDev#123