Fix: `button_padding` when using image+text buttons (#2510)

* feat(image-button-margin): implement image button margin

- add `image_margin` field on `Button` widget
- implement setter method called `image_margin` for `Button` widget
- use margin from `image_margin` field of `Button` widget in `Widget`
  trait functions

* feat(image-button-margin): update changelog

* feat(image-button-margin): implement `map_or` clippy fix

* feat(image-button-margin): remove margin field & fix button-padding instead

* feat(image-button-margin): fix CI errors

* feat(image-button-margin): update changelog to include fix

* feat(image-button-margin): re-add changes after creating screenshots for PR

CHANGELOG.md

@@ -21,6 +21,7 @@ NOTE: [`epaint`](crates/epaint/CHANGELOG.md), [`eframe`](crates/eframe/CHANGELOG
 ### Fixed 🐛
 * Expose `TextEdit`'s multiline flag to AccessKit ([#2448](https://github.com/emilk/egui/pull/2448)).
 * Don't render `\r` (Carriage Return) ([#2452](https://github.com/emilk/egui/pull/2452)).
+* The `button_padding` style option works closer as expected with image+text buttons now ([#2510](https://github.com/emilk/egui/pull/2510)).
 
 
 ## 0.20.1 - 2022-12-11 - Fix key-repeat

crates/egui/src/widgets/button.rs

@@ -221,7 +221,10 @@ impl Widget for Button {
 
             if let Some(image) = image {
                 let image_rect = Rect::from_min_size(
-                    pos2(rect.min.x, rect.center().y - 0.5 - (image.size().y / 2.0)),
+                    pos2(
+                        rect.min.x + button_padding.x,
+                        rect.center().y - 0.5 - (image.size().y / 2.0),
+                    ),
                     image.size(),
                 );
                 image.paint_at(ui, image_rect);