fix(splitter): add touch-action: none style to splitbar

The touch-action none is now enforced through the themes rather than with a utility class

Author: TeyaVes

packages/default/scss/splitter/_layout.scss

@@ -47,6 +47,7 @@
         outline: 0;
         position: absolute;
         user-select: none;
+        touch-action: none;
         display: flex;
         align-items: center;
         justify-content: center;

packages/fluent/scss/splitter/_layout.scss

@@ -46,6 +46,7 @@
         outline: 0;
         position: absolute;
         user-select: none;
+        touch-action: none;
         display: flex;
         align-items: center;
         justify-content: center;