t5551: fix the 50,000 tag test

The first version of test 23 did simply check that no output was
sent to the standard error stream.  With 5e2c7cd2 (t5551: do not use
unportable sed '\+', 2013-05-12), we started to also verify that the
expected tags were actually cloned.

Since 68b939b2 (clone: send diagnostic messages to stderr,
2013-09-18), "git clone" shows "Cloning into 'too-many-refs'" to the
standard error stream (it used to do so to the standard output),
causing the test to fail.

Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t5551-http-fetch.sh

@@ -214,8 +214,7 @@ test_expect_success EXPENSIVE 'create 50,000 tags in the repo' '
 '
 
 test_expect_success EXPENSIVE 'clone the 50,000 tag repo to check OS command line overflow' '
-	git clone $HTTPD_URL/smart/repo.git too-many-refs 2>err &&
-	test_line_count = 0 err &&
+	git clone $HTTPD_URL/smart/repo.git too-many-refs &&
 	(
 		cd too-many-refs &&
 		test $(git for-each-ref refs/tags | wc -l) = 50000