ui: Add text_ellipsis method to Labels (#22118)

This PR adds a `text_ellipsis` method to `Label`s.

This can be used to truncate the text with an ellipsis without needing
to wrap the `Label` in another element.

Release Notes:

- N/A

crates/ui/src/components/label/label.rs

@@ -164,6 +164,11 @@ impl LabelCommon for Label {
         self
     }
 
+    fn text_ellipsis(mut self) -> Self {
+        self.base = self.base.text_ellipsis();
+        self
+    }
+
     fn single_line(mut self) -> Self {
         self.single_line = true;
         self.base = self.base.single_line();