fix(grid): remove column actions input field negative margin (#15950)

Author: adrianptrv

projects/igniteui-angular/src/lib/core/styles/components/column-actions/_column-actions-theme.scss

@@ -100,7 +100,7 @@
 
     %column-actions-input {
         font-size: rem(16px) !important;
-        margin: rem(-16px) 0 0 !important;
+        margin: 0 !important;
         padding: rem(8px) rem(16px);
     }