t4108: use `test_config` instead of `git config`

Since `git config` leaves the configurations set even after the test
case completes, use `test_config` instead so that the configurations are
reset once the test case finishes.

Signed-off-by: Denton Liu <liu.denton@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/t/t4108-apply-threeway.sh b/t/t4108-apply-threeway.sh
index 3c0ddac..7f96ae9 100755 (executable)
--- a/t/t4108-apply-threeway.sh
+++ b/t/t4108-apply-threeway.sh
@@ -70,7 +70,7 @@ test_expect_success 'apply with --3way' '
 '
 
 test_expect_success 'apply with --3way with rerere enabled' '
-       git config rerere.enabled true &&
+       test_config rerere.enabled true &&
 
        # Merging side should be similar to applying this patch
        git diff ...side >P.diff &&