Revert incorrect Rect2.expand description.

[Mickeon]

As you can see here: #69816 (comment)

I am pretty sure this change is wrong. It was specifically modified because, when expanded to the right or bottom, the to point is not included in the rectangle by the has_point. (and this is on purpose)

Agh, this reply is technically correct. Saying "expanded to include" does imply that by calling has_point with the same point on the new rectangle , the result may or may not be true. I would like to think of a way to say this in a simpler way. At worst, the description needs to be mostly reverted back.

This PR reverts the description to say "align the" with a bit of tweaking to have it match the previous changes.

Also affects Rect2i of course.

[akien-mga]

Thanks!