Update docs of `Surface.get_(f)rect()` and `(F)Rect.move_to()`

[damusss]

As you can see from the changed docs I think I made them clearer. I didn't know you could pass size kwargs myself for a long time. The docs technically didn't hide them, but it's very unclear that they do that. Why?

• Surface.get_rect -> it says the rect will have the surface dimentions, so intuitively you'd think you can't resize it
• Rect.move_to -> the name and the docs only mentions that the rect will be moved to a new position, not that it will also resize it.

Yes, they both say that the kwargs should match the attributes and they don't say those are not allowed, but I think this small update makes it more clear.

[ankith26]

Merging this PR in now.

PS: we are on a merge freeze for the 2.5.0 release, so when this PR is merged onto main it will get released in the upcoming 2.5.1 release