fix(elements): add export for DefaultMergeStrategy - 20.1.x#16335

ChronosSF merged 3 commits into20.1.xIgniteUI/igniteui-angular:20.1.xfrom

iminchev/default-merge-strategy-elementsIgniteUI/igniteui-angular:iminchev/default-merge-strategy-elementsCopy head branch name to clipboard