[libadwaita/libadwaita-1-2] stylesheet: Fix spinbuttons inside toolbars

[Alexander Mikhaylenko <alexm src gnome org>]

commit ae1e41053f8c845ff885639e1d69d1050c7eb3b9
Author: Alexander Mikhaylenko <alexm gnome org>
Date:   Wed Sep 14 23:52:20 2022 +0400

    stylesheet: Fix spinbuttons inside toolbars
    
    
    (cherry picked from commit c168d47ba3a8f4a00b9d8a155b480fb06496a47b)

 src/stylesheet/widgets/_spin-button.scss | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/src/stylesheet/widgets/_spin-button.scss b/src/stylesheet/widgets/_spin-button.scss
index 9c275e63..0e49d431 100644
--- a/src/stylesheet/widgets/_spin-button.scss
+++ b/src/stylesheet/widgets/_spin-button.scss
@@ -10,6 +10,8 @@ spinbutton {
   > 
button.image-button.down:not(.flat):not(.raised):not(.suggested-action):not(.destructive-action):not(.opaque) 
{
     @extend %button_basic_flat;
 
+    margin: 0;
+
     border-radius: 0;
     box-shadow: none;