fix(ESF): buttons border styles (#14313)

Author: SisIvanova

projects/igniteui-angular/src/lib/core/styles/components/grid/_excel-filtering-theme.scss

@@ -113,15 +113,35 @@
             --item-hover-background: #{color($color: 'gray', $variant: 100)};
             --item-selected-background: #{color($color: 'gray', $variant: 100)};
             --item-text-color: #{color($color: 'gray', $variant: 700)};
+            --item-icon-color: #{color($color: 'gray', $variant: 700)};
             --item-hover-text-color: #{color($color: 'gray', $variant: 800)};
+            --item-hover-icon-color: #{color($color: 'gray', $variant: 800)};
             --item-selected-text-color: #{if(
                 $variant == 'indigo-design',
                 contrast-color($color: 'surface'),
                 color($color: 'secondary', $variant: 500)
             )};
+            --item-selected-icon-color: #{if(
+                $variant == 'indigo-design',
+                contrast-color($color: 'surface'),
+                color($color: 'secondary', $variant: 500)
+            )};
+            --item-selected-hover-icon-color: #{if(
+                $variant == 'fluent',
+                color($color: 'secondary', $variant: 500),
+                contrast-color($color: 'gray', $variant: 50)
+            )};
             --item-border-color: transparent;
+            --item-hover-border-color: transparent;
+            --item-focused-border-color: #{if(
+                $variant == 'fluent',
+                color($color: 'gray', $variant: 700),
+                transparent
+            )};
             --item-selected-border-color: transparent;
+            --item-selected-hover-border-color: transparent;
             --item-disabled-border: transparent;
+            --disabled-selected-border-color: transparent;
         }
 
         @include tree(tree-theme(