t: fix moderate &&-chain breakage

These are tests which are missing a link in their &&-chain,
but in a way that probably does not effect the outcome of
the test. Most of these are of the form:

  some_cmd >actual
  test_cmp expect actual

The main point of the test is to verify the output, and a
failure in some_cmd would probably be noticed by bogus
output. But it is good for the tests to also confirm that
"some_cmd" does not die unexpectedly after producing its
output.

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

t/t5709-clone-refspec.sh

@@ -147,7 +147,7 @@ test_expect_success '--single-branch with detached' '
 		git for-each-ref refs/remotes/origin |
 		sed -e "/HEAD$/d" \
 		    -e "s|/remotes/origin/|/heads/|" >../actual
-	)
+	) &&
 	# nothing
 	>expect &&
 	test_cmp expect actual