tests: add missing &&

Breaks in a test assertion's && chain can potentially hide
failures from earlier commands in the chain.

Commands intended to fail should be marked with !, test_must_fail, or
test_might_fail.  The examples in this patch do not require that.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/t/t5302-pack-index.sh b/t/t5302-pack-index.sh
index fb3a270..b34ea93 100755
--- a/t/t5302-pack-index.sh
+++ b/t/t5302-pack-index.sh
@@ -8,7 +8,7 @@
 
 test_expect_success \
     'setup' \
-    'rm -rf .git
+    'rm -rf .git &&
      git init &&
      git config pack.threads 1 &&
      i=1 &&