refactor(query-builder): remove _ from the variable name

Author: desig9stein

projects/igniteui-angular/src/lib/core/styles/components/query-builder/_query-builder-theme.scss

@@ -134,9 +134,9 @@
         --_tree-scrollbar-gutter: #{rem(16px)};
 
         @if $variant == 'bootstrap' {
-            --_query-builder-outer-padding: #{rem(16px)};
+            --query-builder-outer-padding: #{rem(16px)};
         } @else {
-            --_query-builder-outer-padding: #{rem(24px)};
+            --query-builder-outer-padding: #{rem(24px)};
         }
 
         width: auto;
@@ -147,18 +147,18 @@
         overflow: hidden;
 
         &:has(:not(igx-query-builder-header)) {
-            padding-block-start: var(--_query-builder-outer-padding);
+            padding-block-start: var(--query-builder-outer-padding);
 
             %query-level-0 {
-                padding-block: 0 var(--_query-builder-outer-padding);
+                padding-block: 0 var(--query-builder-outer-padding);
             }
         }
 
         &:has(igx-query-builder-header) {
             padding-block-start: 0;
 
             %query-level-0 {
-                padding-block: if($variant != 'bootstrap', 0, rem(16px)) var(--_query-builder-outer-padding);
+                padding-block: if($variant != 'bootstrap', 0, rem(16px)) var(--query-builder-outer-padding);
             }
         }
 
@@ -179,7 +179,7 @@
         display: block;
         width: 100%;
 
-        padding-inline: var(--_query-builder-outer-padding);
+        padding-inline: var(--query-builder-outer-padding);
 
         > %advanced-filter__main {
             gap: rem(16px);
@@ -261,8 +261,8 @@
         margin-bottom: 0;
         border-block-end: rem(1px) solid var-get($theme, 'header-border');
 
-        padding-inline: var(--_query-builder-outer-padding);
-        padding-block: var(--_query-builder-outer-padding) rem(16px);
+        padding-inline: var(--query-builder-outer-padding);
+        padding-block: var(--query-builder-outer-padding) rem(16px);
     }
 
     %advanced-filter__title {