bump fly
bump fly

Submodule src/github.com/concourse/fly 98813c1..f1d8b5f:
  > kill redundant test; covered by go-interact
  > fix configuring windows' home directory

cjcjameson/concourse,zachgersh/concourse,cjcjameson/concourse,zachgersh/concourse,cjcjameson/concourse,concourse/concourse,concourse/concourse,CloudCredo/concourse,concourse/concourse,zachgersh/concourse,longnguyen11288/concourse,concourse/concourse,CloudCredo/concourse,concourse/concourse,CloudCredo/concourse,longnguyen11288/concourse,longnguyen11288/concourse