fix: fix missing slds-size selectors @W-12982157@ [backport] (#5182)

Author: nolanlawson

ui/utilities/sizing/_index.scss

@@ -20,7 +20,7 @@ $_sizes: (
 /// @private
 @function all-sizes () {
   $prefixes: 'slds-size_', 'slds-size--';
-  $columnSizes: 2, 3, 4, 5, 6, 7, 8, 12;
+  $columnSizes: 1, 2, 3, 4, 5, 6, 7, 8, 12;
 
   $result: '';
   @each $prefix in $prefixes {