fix typo in Getting Started docs prose
fix typo in Getting Started docs prose

BS3 commits: a96aff1e564227cc03f10aa757ff5c2b80c482b1

todc/todc-bootstrap,ztx1491/todc-bootstrap,up2vs/todc-bootstrap,2947721120/googlebt4,aaroncnhk/todc-bootstrap,todc/todc-bootstrap,todc/todc-bootstrap,mozillo/todc-bootstrap,2947721120/todc-bootstrap