dashboard/app: use newer APIs now that appengine is no longer on 1.6
dashboard/app: use newer APIs now that appengine is no longer on 1.6

xairy/syzkaller,xairy/syzkaller,xairy/syzkaller,google/syzkaller,xairy/syzkaller,google/syzkaller,xairy/syzkaller,google/syzkaller,google/syzkaller,xairy/syzkaller,google/syzkaller,google/syzkaller,xairy/syzkaller,google/syzkaller