Fix value in Dropdown focusOnMount prop

The currently supported values are 'firstElement' | boolean
Based on the JS doc and my testing, we need to use true
to hide the popup on click elsewhere or by ESC.
[MAILPOET-5714]

mailpoet/assets/js/src/automation/editor/components/filters/chip.tsx

@@ -33,7 +33,7 @@ export function FiltersChip({ step, strings }: Props): JSX.Element | null {
 
   return (
     <Dropdown
-      focusOnMount="container"
+      focusOnMount
       popoverProps={{ offset: 6 }}
       renderToggle={({ onToggle, isOpen }) => (
         <Chip