t5510: ensure we stay in the toplevel test dir

The last test descended into a subdir without ever re-emerging, which
is not so nice to the next test writer.

Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/t/t5510-fetch.sh b/t/t5510-fetch.sh
index 6508d8a..d7eca5d 100755
--- a/t/t5510-fetch.sh
+++ b/t/t5510-fetch.sh
@@ -430,14 +430,16 @@
 '
 
 test_expect_success "should be able to fetch with duplicate refspecs" '
-        mkdir dups &&
-        cd dups &&
-        git init &&
-        git config branch.master.remote three &&
-        git config remote.three.url ../three/.git &&
-        git config remote.three.fetch +refs/heads/*:refs/remotes/origin/* &&
-        git config --add remote.three.fetch +refs/heads/*:refs/remotes/origin/* &&
-        git fetch three
+	mkdir dups &&
+	(
+		cd dups &&
+		git init &&
+		git config branch.master.remote three &&
+		git config remote.three.url ../three/.git &&
+		git config remote.three.fetch +refs/heads/*:refs/remotes/origin/* &&
+		git config --add remote.three.fetch +refs/heads/*:refs/remotes/origin/* &&
+		git fetch three
+	)
 '
 
 test_done