Fix t5303 (the test case for pack corruptions) on Windows

[Alex Riesen <raa.lkml@gmail.com>]

The perldiag(1) has following to say about this:

    "Can't do inplace edit without backup"

	(F) You're on a system such as MS-DOS that gets confused if
	you try reading from a deleted (but still opened) file. You
	have to say -i.bak, or some such.

Signed-off-by: Alex Riesen <raa.lkml@gmail.com>
---

 t/t5303-pack-corruption-resilience.sh |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/t/t5303-pack-corruption-resilience.sh b/t/t5303-pack-corruption-resilience.sh
index b0f5693..31b20b2 100755
--- a/t/t5303-pack-corruption-resilience.sh
+++ b/t/t5303-pack-corruption-resilience.sh
@@ -90,7 +90,7 @@ test_expect_success \
     'create_new_pack &&
      git prune-packed &&
      chmod +w ${pack}.pack &&
-     perl -i -pe "s/ base /abcdef/" ${pack}.pack &&
+     perl -i.bak -pe "s/ base /abcdef/" ${pack}.pack &&
      test_must_fail git cat-file blob $blob_1 > /dev/null &&
      test_must_fail git cat-file blob $blob_2 > /dev/null &&
      test_must_fail git cat-file blob $blob_3 > /dev/null'
@@ -138,7 +138,7 @@ test_expect_success \
     'create_new_pack &&
      git prune-packed &&
      chmod +w ${pack}.pack &&
-     perl -i -pe "s/ delta1 /abcdefgh/" ${pack}.pack &&
+     perl -i.bak -pe "s/ delta1 /abcdefgh/" ${pack}.pack &&
      git cat-file blob $blob_1 > /dev/null &&
      test_must_fail git cat-file blob $blob_2 > /dev/null &&
      test_must_fail git cat-file blob $blob_3 > /dev/null'
-- 
1.5.6.28.g6f71b