fix: Apply minor suggestions from code review

Co-authored-by: Copilot <[email protected]>

Author: milan-w

packages/components/src/components/tab-item/tab-item.lite.tsx

@@ -129,7 +129,7 @@ export default function DBTabItem(props: DBTabItemProps) {
 	}, [props.name]);
 
 	onUnMount(() => {
-		if (state._listenerAdded && _ref) {
+		if (state._listenerAdded && _ref && state.boundSetSelectedOnChange) {
 			_ref.closest('[role=tablist]')?.removeEventListener(
 				'change',
 				state.boundSetSelectedOnChange

packages/components/src/components/tabs/tabs.spec.tsx

@@ -9,7 +9,7 @@ import { DBTabList } from '../tab-list';
 import { DBTabPanel } from '../tab-panel';
 
 let tabIndex: number | undefined;
-let comp: any;
+let comp: any = null;
 
 test.beforeEach(() => {
 	tabIndex = undefined;