function escapeHtml(unsafe) {
    if (typeof unsafe !== 'string') {
        return '';
    }
    return unsafe
        .replace(/&/g, '&amp;')
        .replace(/</g, '&lt;')
        .replace(/>/g, '&gt;')
        .replace(/"/g, '&quot;')
        .replace(/'/g, '&#039;');
}
checkss the input is safe or not
@param {HTML} unsafe - the html which we wants to escape
@category ux