contrib/subtree: use tabs consitently for indentation in tests
contrib/subtree: use tabs consitently for indentation in tests

Although subtrees tests uses more spaces for indentation than tabs,
there are still quite a lot of lines indented with tabs. As tabs conform
with Git coding guidelines resolve the inconsistency in favour of tabs.

Signed-off-by: Charles Bailey <3f465f92b896a0cffa56d66f3cf7f14fc3025706@bloomberg.net>
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