Add missed `required` attr in #170
Add missed `required` attr in #170

Would apply better UX to Join Team w/ empty password attempt

royragsdale/picoCTF,picoCTF/picoCTF,royragsdale/picoCTF,royragsdale/picoCTF,picoCTF/picoCTF,royragsdale/picoCTF,picoCTF/picoCTF,picoCTF/picoCTF,royragsdale/picoCTF,picoCTF/picoCTF,royragsdale/picoCTF,picoCTF/picoCTF,royragsdale/picoCTF