ENH: improve support for Path objects in io.ascii.core.BaseInputter.get_lines - #16930

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RTD is failing... presumably unrelated but I don't have the power to get around that.

whoops. It is actually related

<unknown>:20: WARNING: py:obj reference target not found: io.ascii.core.BaseInputter.get_lines [ref.obj]

Let me try and fix the changelog fragment.

CI green now. @taldcroft do you want to re-review?

@taldcroft or feel free to move this to 7.1

We're hours away from astropy 7.0's feature freeze and this shouldn't be blocking in any way, so I'll bump the milestone to clear the backlog. If this happened to be merged today anyway, please revert the milestone.