Merge pull request #10755 from overleaf/jel-btn-border

[web] Only set a border size for buttons using mixins on new CSS

GitOrigin-RevId: c6c2ce4f43f038601e52c580ba8b10981bb59317

services/web/frontend/stylesheets/components/buttons.less

@@ -59,7 +59,7 @@
   text-align: center;
   vertical-align: middle;
   cursor: pointer;
-  border: @border-size solid transparent;
+  border: 0 solid transparent;
   white-space: nowrap;
   .button-size(
     @padding-base-vertical; @padding-base-horizontal; @font-size-base;

services/web/frontend/stylesheets/core/mixins.less

@@ -553,6 +553,7 @@
   color: @content-primary;
   background-color: @white;
   border-color: @border-color-base;
+  border-width: @border-size;
 
   &:hover {
     background-color: @btn-secondary-hover-bg-color;
@@ -594,6 +595,7 @@
   color: @color;
   background-color: @background;
   border-color: @background; // add a border that is same as background color so that the height matches the btn-bordered style
+  border-width: @border-size;
 
   &:hover {
     background-color: @background-hover;