Fixed minor typo
Fixed minor typo

se-edu/addressbook-level1,cheec/addressbook-level2,jasperlee27/addressbook-level1,se-edu/addressbook-level1,se-edu/addressbook-level2,se-edu/addressbook-level2,zachylimwl/addressbook-level2,imhongw/addressbook-level2,imhongw/addressbook-level2,mingruimingrui/addressbook-level2,zachylimwl/addressbook-level2,jasperlee27/addressbook-level1,mingruimingrui/addressbook-level2,cheec/addressbook-level2