Size::height sets width not height (#7478)

# Objective
```rust
pub const fn height(width: Val) -> Self {
        Self {
            width,
            height: Val::DEFAULT,
        }
    }
```
😓

## Solution
Swap `width` and `height`.

crates/bevy_ui/src/geometry.rs

@@ -374,10 +374,10 @@ impl Size {
     }
 
     /// Creates a new [`Size`] where `height` takes the given value.
-    pub const fn height(width: Val) -> Self {
+    pub const fn height(height: Val) -> Self {
         Self {
-            width,
+            width: Val::DEFAULT,
-            height: Val::DEFAULT,
+            height,
         }
     }