t5521: test --dry-run does not make any changes
t5521: test --dry-run does not make any changes

Test that when --dry-run is provided to git-pull, it does not make any
changes, namely:

* --dry-run gets passed to git-fetch, so no FETCH_HEAD will be created
  and no refs will be fetched.

* The index and work tree will not be modified.

Signed-off-by: Paul Tan <ca5433e1cdd25b4a4001c54525dea593b33edc0c@gmail.com>
Signed-off-by: Junio C Hamano <a6723cc3f76163bf7adb636a73ac3b0ceb3e6b9b@pobox.com>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git