t7607: clean up stray untracked file

This file ends up conflicting with the test just after it
(causing the "git merge" to fail).  Neither test is to blame
for the bug, though. It looks like the merge in 1a9fe45
(Merge branch 'tr/merge-unborn-clobber', 2011-02-09) is what
caused the conflict.

We didn't notice because the follow-on test is already
marked as expect_failure (even though it has since been
fixed, and now succeeds once the untracked file is moved out
of the way).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t7607-merge-overwrite.sh

@@ -150,6 +150,7 @@ test_expect_success 'will not overwrite untracked file on unborn branch' '
 	git rm -fr . &&
 	git checkout --orphan new &&
 	cp important c0.c &&
+	test_when_finished "rm c0.c" &&
 	test_must_fail git merge c0 2>out &&
 	test_cmp out expect &&
 	test_path_is_missing .git/MERGE_HEAD &&
@@ -164,7 +165,7 @@ test_expect_success 'set up unborn branch and content' '
 	echo bar > untracked-file
 '
 
-test_expect_failure 'will not clobber WT/index when merging into unborn' '
+test_expect_success 'will not clobber WT/index when merging into unborn' '
 	git merge master &&
 	grep foo tracked-file &&
 	git show :tracked-file >expect &&