Stop a findInPage call by specifying any of these actions:
- clearSelection - Clear the selection.
 - keepSelection - Translate the selection into a normal selection.
 - activateSelection - Focus and click the selection node.
 
Example
const win = fin.Window.getCurrentSync();
win.addListener('found-in-page', (event) => {
    setTimeout(() => {
        win.stopFindInPage('clearSelection');
    }, 5000);
});
win.findInPage('a').then(results => {
    console.log(results);
});